64-bit still memory limited?

[Guest Mark]

I'm probably out of my league, but when did that ever stop someone from

posting. (Yes, there is a question at the end of the post.)

[Note: Also posted in General Discussion.]

 

Computers have three main buses:

Control Bus

Data Bus

Address Bus

 

Control Bus is 16 bits wide and tells the address bus what method of

communication is required (32-bit or 48-bit)for the device currently seeking

to control the data bus.

 

Data Bus is 64-bits wide, but typically cannot find anything to talk to

wider than 32-bits other than the main processor which for most systems is

also working in 32-bit mode.

 

Address Bus is 48-bits wide and typically operates in one of two modes:

32-bit or 48-bit. This method of operation depends on the Control Bus'

instructions. 32-bit for peripheral devices. 48-bit for the main processor.

In theory, 48-bit could access 2^48 addresses. (65,536 * 4GB) But, those

darned peripheral chips force the control bus to limit the address bus to

32-bit or 4GB.

 

Peripheral devices (video card, sound card, modem, etc.) are hard coded to

work in 32-bit. If your OS is 64-bit, then the drivers must be in 64-bit to

ensure information sent to the peripheral device is formatted in a manner it

can understand. Information from the device must be padded to 64-bit. And the

control bus must be told it is still a 32-bit device. If the device is

actually a 64-bit device (extremely rare) then the control bus is told it is

a 64-bit device and lets the address bus do it's thing.

 

But, 32-bit hardware changes how the address bus works. (Fixed with 64-bit

drivers.) The upper 16 bits of the address bus become a means of identifying

the device, mode of communication, etc. (essentially, paging mode for these

devices to allow more than 4GB of memory to be addressed) and shift data

transfer to a two iteration process (slowing things down.) Vendors understand

this and design hardware to gain the speed of the processor by memory-mapping

their hardware into RAM addresses so that the address bus does not shift to

two step mode when sending or retrieving information to and from that device.

This memory mapping reduces available RAM since the addresses cannot exist in

duplicate.

 

Based on this (probably flawed logic), it does not appear to me that

converting to 64-bit Vista will improve my memory situation unless I actually

install more than 4GB of memory to get above the peripheral devices memory

mapping "window." Until then, the memory mapping of the peripheral devices

still eats the RAM between 3GB and 4GB.

 

Is this correct?

Are 64-bit Vista users seeing 4 GB of RAM or the 3.2 GB "limit" with 4GB of

RAM installed?

[Guest Maratonmannen]

RE: 64-bit still memory limited?

 

My Vista Ultimate, Business and Windows Server 2008 x64 systems are all seing

my 4 GB RAM.

It has been this way since day 1, two years ago.

Intel chipsets (i955X and i975X), no memory remapping setting in BIOS.

 

--

Asus P5WDG2 WS Pro (i975X Express)

Core™ 2 Extreme X6800

RAPTOR 2x150 GB RAID 0

4GB DDR2 800MHz

GeForce 8800GTX (163.11+165.01)

Enermax 1000W 75A@+12V

LAN 100/100

XP x64 dualboot Vista x64

 

 

"Mark" wrote:

> I'm probably out of my league, but when did that ever stop someone from

> posting. (Yes, there is a question at the end of the post.)

> [Note: Also posted in General Discussion.]

>

> Computers have three main buses:

> Control Bus

> Data Bus

> Address Bus

>

> Control Bus is 16 bits wide and tells the address bus what method of

> communication is required (32-bit or 48-bit)for the device currently seeking

> to control the data bus.

>

> Data Bus is 64-bits wide, but typically cannot find anything to talk to

> wider than 32-bits other than the main processor which for most systems is

> also working in 32-bit mode.

>

> Address Bus is 48-bits wide and typically operates in one of two modes:

> 32-bit or 48-bit. This method of operation depends on the Control Bus'

> instructions. 32-bit for peripheral devices. 48-bit for the main processor.

> In theory, 48-bit could access 2^48 addresses. (65,536 * 4GB) But, those

> darned peripheral chips force the control bus to limit the address bus to

> 32-bit or 4GB.

>

> Peripheral devices (video card, sound card, modem, etc.) are hard coded to

> work in 32-bit. If your OS is 64-bit, then the drivers must be in 64-bit to

> ensure information sent to the peripheral device is formatted in a manner it

> can understand. Information from the device must be padded to 64-bit. And the

> control bus must be told it is still a 32-bit device. If the device is

> actually a 64-bit device (extremely rare) then the control bus is told it is

> a 64-bit device and lets the address bus do it's thing.

>

> But, 32-bit hardware changes how the address bus works. (Fixed with 64-bit

> drivers.) The upper 16 bits of the address bus become a means of identifying

> the device, mode of communication, etc. (essentially, paging mode for these

> devices to allow more than 4GB of memory to be addressed) and shift data

> transfer to a two iteration process (slowing things down.) Vendors understand

> this and design hardware to gain the speed of the processor by memory-mapping

> their hardware into RAM addresses so that the address bus does not shift to

> two step mode when sending or retrieving information to and from that device.

> This memory mapping reduces available RAM since the addresses cannot exist in

> duplicate.

>

> Based on this (probably flawed logic), it does not appear to me that

> converting to 64-bit Vista will improve my memory situation unless I actually

> install more than 4GB of memory to get above the peripheral devices memory

> mapping "window." Until then, the memory mapping of the peripheral devices

> still eats the RAM between 3GB and 4GB.

>

> Is this correct?

> Are 64-bit Vista users seeing 4 GB of RAM or the 3.2 GB "limit" with 4GB of

> RAM installed?

>

[Guest Mark]

RE: 64-bit still memory limited?

 

Thanks!

I'm assuming the two years ago wasn't Vista... :-)

 

"Maratonmannen" wrote:

> My Vista Ultimate, Business and Windows Server 2008 x64 systems are all seing

> my 4 GB RAM.

> It has been this way since day 1, two years ago.

> Intel chipsets (i955X and i975X), no memory remapping setting in BIOS.

>

> --

> Asus P5WDG2 WS Pro (i975X Express)

> Core™ 2 Extreme X6800

> RAPTOR 2x150 GB RAID 0

> 4GB DDR2 800MHz

> GeForce 8800GTX (163.11+165.01)

> Enermax 1000W 75A@+12V

> LAN 100/100

> XP x64 dualboot Vista x64

>

>

> "Mark" wrote:

>

> > I'm probably out of my league, but when did that ever stop someone from

> > posting. (Yes, there is a question at the end of the post.)

> > [Note: Also posted in General Discussion.]

> >

> > Computers have three main buses:

> > Control Bus

> > Data Bus

> > Address Bus

> >

> > Control Bus is 16 bits wide and tells the address bus what method of

> > communication is required (32-bit or 48-bit)for the device currently seeking

> > to control the data bus.

> >

> > Data Bus is 64-bits wide, but typically cannot find anything to talk to

> > wider than 32-bits other than the main processor which for most systems is

> > also working in 32-bit mode.

> >

> > Address Bus is 48-bits wide and typically operates in one of two modes:

> > 32-bit or 48-bit. This method of operation depends on the Control Bus'

> > instructions. 32-bit for peripheral devices. 48-bit for the main processor.

> > In theory, 48-bit could access 2^48 addresses. (65,536 * 4GB) But, those

> > darned peripheral chips force the control bus to limit the address bus to

> > 32-bit or 4GB.

> >

> > Peripheral devices (video card, sound card, modem, etc.) are hard coded to

> > work in 32-bit. If your OS is 64-bit, then the drivers must be in 64-bit to

> > ensure information sent to the peripheral device is formatted in a manner it

> > can understand. Information from the device must be padded to 64-bit. And the

> > control bus must be told it is still a 32-bit device. If the device is

> > actually a 64-bit device (extremely rare) then the control bus is told it is

> > a 64-bit device and lets the address bus do it's thing.

> >

> > But, 32-bit hardware changes how the address bus works. (Fixed with 64-bit

> > drivers.) The upper 16 bits of the address bus become a means of identifying

> > the device, mode of communication, etc. (essentially, paging mode for these

> > devices to allow more than 4GB of memory to be addressed) and shift data

> > transfer to a two iteration process (slowing things down.) Vendors understand

> > this and design hardware to gain the speed of the processor by memory-mapping

> > their hardware into RAM addresses so that the address bus does not shift to

> > two step mode when sending or retrieving information to and from that device.

> > This memory mapping reduces available RAM since the addresses cannot exist in

> > duplicate.

> >

> > Based on this (probably flawed logic), it does not appear to me that

> > converting to 64-bit Vista will improve my memory situation unless I actually

> > install more than 4GB of memory to get above the peripheral devices memory

> > mapping "window." Until then, the memory mapping of the peripheral devices

> > still eats the RAM between 3GB and 4GB.

> >

> > Is this correct?

> > Are 64-bit Vista users seeing 4 GB of RAM or the 3.2 GB "limit" with 4GB of

> > RAM installed?

> >

[Guest Maratonmannen]

RE: 64-bit still memory limited?

 

It was Vista.

I was a beta-tester from the beginning. And I always did run 64-bit, just to

see my all 4. :)

 

--

Asus P5WDG2 WS Pro (i975X Express)

Core™ 2 Extreme X6800

RAPTOR 2x150 GB RAID 0

4GB DDR2 800MHz

GeForce 8800GTX (162.18+165.01)

Enermax 1000W 75A@+12V

LAN 100/100

XP x64 dualboot Vista x64

 

 

"Mark" wrote:

> Thanks!

> I'm assuming the two years ago wasn't Vista... :-)

>

> "Maratonmannen" wrote:

>

> > My Vista Ultimate, Business and Windows Server 2008 x64 systems are all seing

> > my 4 GB RAM.

> > It has been this way since day 1, two years ago.

> > Intel chipsets (i955X and i975X), no memory remapping setting in BIOS.

> >

> > --

> > Asus P5WDG2 WS Pro (i975X Express)

> > Core™ 2 Extreme X6800

> > RAPTOR 2x150 GB RAID 0

> > 4GB DDR2 800MHz

> > GeForce 8800GTX (163.11+165.01)

> > Enermax 1000W 75A@+12V

> > LAN 100/100

> > XP x64 dualboot Vista x64

> >

> >

> > "Mark" wrote:

> >

> > > I'm probably out of my league, but when did that ever stop someone from

> > > posting. (Yes, there is a question at the end of the post.)

> > > [Note: Also posted in General Discussion.]

> > >

> > > Computers have three main buses:

> > > Control Bus

> > > Data Bus

> > > Address Bus

> > >

> > > Control Bus is 16 bits wide and tells the address bus what method of

> > > communication is required (32-bit or 48-bit)for the device currently seeking

> > > to control the data bus.

> > >

> > > Data Bus is 64-bits wide, but typically cannot find anything to talk to

> > > wider than 32-bits other than the main processor which for most systems is

> > > also working in 32-bit mode.

> > >

> > > Address Bus is 48-bits wide and typically operates in one of two modes:

> > > 32-bit or 48-bit. This method of operation depends on the Control Bus'

> > > instructions. 32-bit for peripheral devices. 48-bit for the main processor.

> > > In theory, 48-bit could access 2^48 addresses. (65,536 * 4GB) But, those

> > > darned peripheral chips force the control bus to limit the address bus to

> > > 32-bit or 4GB.

> > >

> > > Peripheral devices (video card, sound card, modem, etc.) are hard coded to

> > > work in 32-bit. If your OS is 64-bit, then the drivers must be in 64-bit to

> > > ensure information sent to the peripheral device is formatted in a manner it

> > > can understand. Information from the device must be padded to 64-bit. And the

> > > control bus must be told it is still a 32-bit device. If the device is

> > > actually a 64-bit device (extremely rare) then the control bus is told it is

> > > a 64-bit device and lets the address bus do it's thing.

> > >

> > > But, 32-bit hardware changes how the address bus works. (Fixed with 64-bit

> > > drivers.) The upper 16 bits of the address bus become a means of identifying

> > > the device, mode of communication, etc. (essentially, paging mode for these

> > > devices to allow more than 4GB of memory to be addressed) and shift data

> > > transfer to a two iteration process (slowing things down.) Vendors understand

> > > this and design hardware to gain the speed of the processor by memory-mapping

> > > their hardware into RAM addresses so that the address bus does not shift to

> > > two step mode when sending or retrieving information to and from that device.

> > > This memory mapping reduces available RAM since the addresses cannot exist in

> > > duplicate.

> > >

> > > Based on this (probably flawed logic), it does not appear to me that

> > > converting to 64-bit Vista will improve my memory situation unless I actually

> > > install more than 4GB of memory to get above the peripheral devices memory

> > > mapping "window." Until then, the memory mapping of the peripheral devices

> > > still eats the RAM between 3GB and 4GB.

> > >

> > > Is this correct?

> > > Are 64-bit Vista users seeing 4 GB of RAM or the 3.2 GB "limit" with 4GB of

> > > RAM installed?

> > >

[Guest miso@sushi.com]

Re: 64-bit still memory limited?

 

On Aug 15, 12:10 pm, Maratonmannen

<Maratonman...@discussions.microsoft.com> wrote:

> It was Vista.

> I was a beta-tester from the beginning. And I always did run 64-bit, just to

> see my all 4. :)

>

> --

> Asus P5WDG2 WS Pro (i975X Express)

> Core™ 2 Extreme X6800

> RAPTOR 2x150 GB RAID 0

> 4GB DDR2 800MHz

> GeForce 8800GTX (162.18+165.01)

> Enermax 1000W 75A@+12V

> LAN 100/100

> XP x64 dualboot Vista x64

>

> "Mark" wrote:

> > Thanks!

> > I'm assuming the two years ago wasn't Vista... :-)

>

> > "Maratonmannen" wrote:

>

> > > My Vista Ultimate, Business and Windows Server 2008 x64 systems are all seing

> > > my 4 GB RAM.

> > > It has been this way since day 1, two years ago.

> > > Intel chipsets (i955X and i975X), no memory remapping setting in BIOS.

>

> > > --

> > > Asus P5WDG2 WS Pro (i975X Express)

> > > Core™ 2 Extreme X6800

> > > RAPTOR 2x150 GB RAID 0

> > > 4GB DDR2 800MHz

> > > GeForce 8800GTX (163.11+165.01)

> > > Enermax 1000W 75A@+12V

> > > LAN 100/100

> > > XP x64 dualboot Vista x64

>

> > > "Mark" wrote:

>

> > > > I'm probably out of my league, but when did that ever stop someone from

> > > > posting. (Yes, there is a question at the end of the post.)

> > > > [Note: Also posted in General Discussion.]

>

> > > > Computers have three main buses:

> > > > Control Bus

> > > > Data Bus

> > > > Address Bus

>

> > > > Control Bus is 16 bits wide and tells the address bus what method of

> > > > communication is required (32-bit or 48-bit)for the device currently seeking

> > > > to control the data bus.

>

> > > > Data Bus is 64-bits wide, but typically cannot find anything to talk to

> > > > wider than 32-bits other than the main processor which for most systems is

> > > > also working in 32-bit mode.

>

> > > > Address Bus is 48-bits wide and typically operates in one of two modes:

> > > > 32-bit or 48-bit. This method of operation depends on the Control Bus'

> > > > instructions. 32-bit for peripheral devices. 48-bit for the main processor.

> > > > In theory, 48-bit could access 2^48 addresses. (65,536 * 4GB) But, those

> > > > darned peripheral chips force the control bus to limit the address bus to

> > > > 32-bit or 4GB.

>

> > > > Peripheral devices (video card, sound card, modem, etc.) are hard coded to

> > > > work in 32-bit. If your OS is 64-bit, then the drivers must be in 64-bit to

> > > > ensure information sent to the peripheral device is formatted in a manner it

> > > > can understand. Information from the device must be padded to 64-bit. And the

> > > > control bus must be told it is still a 32-bit device. If the device is

> > > > actually a 64-bit device (extremely rare) then the control bus is told it is

> > > > a 64-bit device and lets the address bus do it's thing.

>

> > > > But, 32-bit hardware changes how the address bus works. (Fixed with 64-bit

> > > > drivers.) The upper 16 bits of the address bus become a means of identifying

> > > > the device, mode of communication, etc. (essentially, paging mode for these

> > > > devices to allow more than 4GB of memory to be addressed) and shift data

> > > > transfer to a two iteration process (slowing things down.) Vendors understand

> > > > this and design hardware to gain the speed of the processor by memory-mapping

> > > > their hardware into RAM addresses so that the address bus does not shift to

> > > > two step mode when sending or retrieving information to and from that device.

> > > > This memory mapping reduces available RAM since the addresses cannot exist in

> > > > duplicate.

>

> > > > Based on this (probably flawed logic), it does not appear to me that

> > > > converting to 64-bit Vista will improve my memory situation unless I actually

> > > > install more than 4GB of memory to get above the peripheral devices memory

> > > > mapping "window." Until then, the memory mapping of the peripheral devices

> > > > still eats the RAM between 3GB and 4GB.

>

> > > > Is this correct?

> > > > Are 64-bit Vista users seeing 4 GB of RAM or the 3.2 GB "limit" with 4GB of

> > > > RAM installed?

 

As has been mentioned before but is worth repeating, some bios needs

to do a memory remap to see all 4Gbytes. On my Nforce4, I need to do

control-f1 just to see the remap option.

[Guest David Simpson]

Re: 64-bit still memory limited?

 

=?Utf-8?B?TWFyaw==?= <Mark@discussions.microsoft.com> wrote in

news:6102F6E5-0E00-4BD4-A9D4-AB9689CCF3E3@microsoft.com:

> I'm probably out of my league, but when did that ever stop someone

> from posting. (Yes, there is a question at the end of the post.)

> [Note: Also posted in General Discussion.]

 

Not trying to pick on you, but please go take a digital logic class

before someone that's willing to really rip you apart sees this. ;-)

 

> Computers have three main buses:

> Control Bus

> Data Bus

> Address Bus

 

 

> Control Bus is 16 bits wide and tells the address bus what method of

> communication is required (32-bit or 48-bit)for the device currently

> seeking to control the data bus.

>

> Data Bus is 64-bits wide, but typically cannot find anything to talk

> to wider than 32-bits other than the main processor which for most

> systems is also working in 32-bit mode.

 

Oops, you forgot the RAM. 99% of all work done by the CPU is with the

RAM or Cache.

 

> Address Bus is 48-bits wide and typically operates in one of two

> modes: 32-bit or 48-bit. This method of operation depends on the

> Control Bus' instructions. 32-bit for peripheral devices. 48-bit for

> the main processor. In theory, 48-bit could access 2^48 addresses.

> (65,536 * 4GB) But, those darned peripheral chips force the control

> bus to limit the address bus to 32-bit or 4GB.

 

Wrong, because the control bus knows when you are talking to a device or

RAM. When you talk in 48bit mode, it can disable all those.

 

> If your OS is 64-bit, then the drivers must

> be in 64-bit to ensure information sent to the peripheral device is

> formatted in a manner it can understand. Information from the device

> must be padded to 64-bit. And the control bus must be told it is still

> a 32-bit device. If the device is actually a 64-bit device (extremely

> rare) then the control bus is told it is a 64-bit device and lets the

> address bus do it's thing.

 

This is why your OS needs to be 64bit, not the hardware. The DRIVERS

control the devices, and could easily handle the 32/48 bit switching, if

the programmers knew what they were doing. Problem is, most programmer

are VERY lazy, or they would be doing hardware design, not software

design. ;-)

 

Also, most control devices are 8bit (with a few 16bit), not 32bit!

 

 

--

_______________________________________________

/ David Simpson \

| dsimpson@NOnyxSPAM.net |

| http://www.nyx.net/~dsimpson |

|We got to go to the crappy town where I'm a hero.|

\_______________________________________________/

[Guest Mark]

Re: 64-bit still memory limited?

 

I appreciate the corrections!

(Didn't really forget the RAM, just thought of it as part of the main

processor realizing it is more "directly" linked.)

 

The 8-bit comment is a "bit" surprising.

 

 

"David Simpson" <dsimpson@NOnyx.SPAMnet> wrote in message

news:Xns998DA969958C3dsimpsonnyxnetmememe@216.196.97.131...

> =?Utf-8?B?TWFyaw==?= <Mark@discussions.microsoft.com> wrote in

> news:6102F6E5-0E00-4BD4-A9D4-AB9689CCF3E3@microsoft.com:

>

>> I'm probably out of my league, but when did that ever stop someone

>> from posting. (Yes, there is a question at the end of the post.)

>> [Note: Also posted in General Discussion.]

>

> Not trying to pick on you, but please go take a digital logic class

> before someone that's willing to really rip you apart sees this. ;-)

>

>

>> Computers have three main buses:

>> Control Bus

>> Data Bus

>> Address Bus

>

>

>

>> Control Bus is 16 bits wide and tells the address bus what method of

>> communication is required (32-bit or 48-bit)for the device currently

>> seeking to control the data bus.

>>

>> Data Bus is 64-bits wide, but typically cannot find anything to talk

>> to wider than 32-bits other than the main processor which for most

>> systems is also working in 32-bit mode.

>

> Oops, you forgot the RAM. 99% of all work done by the CPU is with the

> RAM or Cache.

>

>

>> Address Bus is 48-bits wide and typically operates in one of two

>> modes: 32-bit or 48-bit. This method of operation depends on the

>> Control Bus' instructions. 32-bit for peripheral devices. 48-bit for

>> the main processor. In theory, 48-bit could access 2^48 addresses.

>> (65,536 * 4GB) But, those darned peripheral chips force the control

>> bus to limit the address bus to 32-bit or 4GB.

>

> Wrong, because the control bus knows when you are talking to a device or

> RAM. When you talk in 48bit mode, it can disable all those.

>

>

>> If your OS is 64-bit, then the drivers must

>> be in 64-bit to ensure information sent to the peripheral device is

>> formatted in a manner it can understand. Information from the device

>> must be padded to 64-bit. And the control bus must be told it is still

>> a 32-bit device. If the device is actually a 64-bit device (extremely

>> rare) then the control bus is told it is a 64-bit device and lets the

>> address bus do it's thing.

>

> This is why your OS needs to be 64bit, not the hardware. The DRIVERS

> control the devices, and could easily handle the 32/48 bit switching, if

> the programmers knew what they were doing. Problem is, most programmer

> are VERY lazy, or they would be doing hardware design, not software

> design. ;-)

>

> Also, most control devices are 8bit (with a few 16bit), not 32bit!

>

>

> --

> _______________________________________________

> / David Simpson \

> | dsimpson@NOnyxSPAM.net |

> | http://www.nyx.net/~dsimpson |

> |We got to go to the crappy town where I'm a hero.|

> \_______________________________________________/

[Guest Tony Sperling]

Re: 64-bit still memory limited?

 

I have to particularily thank you for this lesson, David. I knew I smelled

'fish' but my background is old and muddy. I knew the BIOS is 8bit, but I

wouldn't have thought of it in this context, I assume now that it is

significant? (unless they went and changed that too. . .)

 

 

Tony. . .

[Guest Mark]

Re: 64-bit still memory limited?

 

Okay, you made me look it up!

 

Most of the BIOS chips I looked at (pinouts) had 16-18 bit address buses

and, yes, 8-bit data buses. Of course, it's not really fair to say that the

BIOS is normally operating this way since it transfers itself to RAM and

uses the main processor from that point to perform it's functions. (Never

returning to the actual BIOS chip for help.) The BIOS on the various

peripherals do much the same thing during initial boot. So while there is an

initial flurry of 8-bit activity, it seems to subside rather quickly before

the OS is actually loaded.

 

Once past this point, there is mostly a mixture of 16-bit (few) and 32-bit

(most) data streams from peripherals. (Of course age of computer and

peripherals will determine this mix better.)

 

I should have taken a refresher course. My TRS-80 knowledge is just a little

out of date and just doesn't bridge the gap anymore. Thanks for not beating

me up too much.

 

 

 

"David Simpson" <dsimpson@NOnyx.SPAMnet> wrote in message

news:Xns998DA969958C3dsimpsonnyxnetmememe@216.196.97.131...

> =?Utf-8?B?TWFyaw==?= <Mark@discussions.microsoft.com> wrote in

> news:6102F6E5-0E00-4BD4-A9D4-AB9689CCF3E3@microsoft.com:

>

>> I'm probably out of my league, but when did that ever stop someone

>> from posting. (Yes, there is a question at the end of the post.)

>> [Note: Also posted in General Discussion.]

>

> Not trying to pick on you, but please go take a digital logic class

> before someone that's willing to really rip you apart sees this. ;-)

>

>

>> Computers have three main buses:

>> Control Bus

>> Data Bus

>> Address Bus

>

>

>

>> Control Bus is 16 bits wide and tells the address bus what method of

>> communication is required (32-bit or 48-bit)for the device currently

>> seeking to control the data bus.

>>

>> Data Bus is 64-bits wide, but typically cannot find anything to talk

>> to wider than 32-bits other than the main processor which for most

>> systems is also working in 32-bit mode.

>

> Oops, you forgot the RAM. 99% of all work done by the CPU is with the

> RAM or Cache.

>

>

>> Address Bus is 48-bits wide and typically operates in one of two

>> modes: 32-bit or 48-bit. This method of operation depends on the

>> Control Bus' instructions. 32-bit for peripheral devices. 48-bit for

>> the main processor. In theory, 48-bit could access 2^48 addresses.

>> (65,536 * 4GB) But, those darned peripheral chips force the control

>> bus to limit the address bus to 32-bit or 4GB.

>

> Wrong, because the control bus knows when you are talking to a device or

> RAM. When you talk in 48bit mode, it can disable all those.

>

>

>> If your OS is 64-bit, then the drivers must

>> be in 64-bit to ensure information sent to the peripheral device is

>> formatted in a manner it can understand. Information from the device

>> must be padded to 64-bit. And the control bus must be told it is still

>> a 32-bit device. If the device is actually a 64-bit device (extremely

>> rare) then the control bus is told it is a 64-bit device and lets the

>> address bus do it's thing.

>

> This is why your OS needs to be 64bit, not the hardware. The DRIVERS

> control the devices, and could easily handle the 32/48 bit switching, if

> the programmers knew what they were doing. Problem is, most programmer

> are VERY lazy, or they would be doing hardware design, not software

> design. ;-)

>

> Also, most control devices are 8bit (with a few 16bit), not 32bit!

>

>

> --

> _______________________________________________

> / David Simpson \

> | dsimpson@NOnyxSPAM.net |

> | http://www.nyx.net/~dsimpson |

> |We got to go to the crappy town where I'm a hero.|

> \_______________________________________________/

[Guest David Simpson]

Re: 64-bit still memory limited?

 

"Mark" <jmhonzell.nospam@insightbb.com> wrote in news:#n9#Fx43HHA.4476

@TK2MSFTNGP06.phx.gbl:

> I appreciate the corrections!

> (Didn't really forget the RAM, just thought of it as part of the main

> processor realizing it is more "directly" linked.)

>

> The 8-bit comment is a "bit" surprising.

 

I really wish I could explaine things in better detail. It really 99% an

OS problem, and in a few cases, a 1% hardware problem. (some hardware

designers are lazy)

 

Most hardware still deals with 8 bits at a time. Sure the drivers or

control regusters and buffers are 16, 32 or in the case of video cards even

wider, it the drivers that control everything. M$ just decide that they

wouldn't allow 32 bit driver in the 64 bit OS. Sure you want 64 bit when

you talk to high speed stuff like a video card, but a keyboard? Even a

scanner should be able to the slow down. They just didn't want to write it

that way. From what I've heard, Apple is planning on you being able to use

old 32 bit drivers in the 64 bit OS. That way you don't have to wait for

print drivers that will never be released!

 

 

--

_______________________________________________

/ David Simpson \

| dsimpson@NOnyxSPAM.net |

| http://www.nyx.net/~dsimpson |

|We got to go to the crappy town where I'm a hero.|

\_______________________________________________/

[Guest Mark]

Re: 64-bit still memory limited?

 

Really appreciate the feedback!

So much has changed... and apparently in some areas... not that much.

 

"David Simpson" <dsimpson@NOnyx.SPAMnet> wrote in message

news:Xns998E83FE446BBdsimpsonnyxnetmememe@216.196.97.131...

> "Mark" <jmhonzell.nospam@insightbb.com> wrote in news:#n9#Fx43HHA.4476

> @TK2MSFTNGP06.phx.gbl:

>

>> I appreciate the corrections!

>> (Didn't really forget the RAM, just thought of it as part of the main

>> processor realizing it is more "directly" linked.)

>>

>> The 8-bit comment is a "bit" surprising.

>

> I really wish I could explaine things in better detail. It really 99% an

> OS problem, and in a few cases, a 1% hardware problem. (some hardware

> designers are lazy)

>

> Most hardware still deals with 8 bits at a time. Sure the drivers or

> control regusters and buffers are 16, 32 or in the case of video cards

> even

> wider, it the drivers that control everything. M$ just decide that they

> wouldn't allow 32 bit driver in the 64 bit OS. Sure you want 64 bit when

> you talk to high speed stuff like a video card, but a keyboard? Even a

> scanner should be able to the slow down. They just didn't want to write

> it

> that way. From what I've heard, Apple is planning on you being able to

> use

> old 32 bit drivers in the 64 bit OS. That way you don't have to wait for

> print drivers that will never be released!

>

>

> --

> _______________________________________________

> / David Simpson \

> | dsimpson@NOnyxSPAM.net |

> | http://www.nyx.net/~dsimpson |

> |We got to go to the crappy town where I'm a hero.|

> \_______________________________________________/