OT: Memory expert please :-)

[Guest RJK]

I just bought 2x512 ddr400/pc2300 Corsair XMS 3200LL modules, and after

doing quite a bit

of Googling,

I am no further forward in determing the "best" settings in bios, and

indeed, my bios has slightly ambiguous labels which are hard to match up

with,

tRCD, tRP and tRAS etc.

http://www.techpowerup.com/articles/overclocking/64

i.e Which one is which ?

 

If I set bios to use SPD, Lavalys Everest "motherboard" ICH5 reports :-

Memory Timings:

CAS Latency (CL) 2T

RAS To CAS Delay (tRCD) 2T

RAS Precharge (tRP) 2T

RAS Active Time (tRAS) 5T

???

 

I've just set manually in bios:- (Below is how the bios memory setting

options appear on screen btw),

DRAM CAS# Latency 2.5

DRAM RAS# Precharge 3

DRAM RAS# to CAS# Delay 3

DRAM Precharge Delay 5

DRAM Burst Length 4

....and CPUZ reflects these settings accurately, ...(dunno what Lavalys

Everest is doing ?!)

anyhooo...

....completely confused, after reading lots about setting CAS to 2 can not be

as "good" as setting it to 2.5 ???

 

....any advice much appreciated,

 

TIA

 

regards, Richard

[Guest R. McCarty]

Re: Memory expert please :-)

 

Re: Memory expert please :-)

 

You may get more helpful info from the OverClockers forum:

http://www.ocforums.com/ (Memory)

 

"RJK" <nospam@hotmail.com> wrote in message

news:eoxfBfH0IHA.4876@TK2MSFTNGP04.phx.gbl...

>I just bought 2x512 ddr400/pc2300 Corsair XMS 3200LL modules, and after

>doing quite a bit

> of Googling,

> I am no further forward in determing the "best" settings in bios, and

> indeed, my bios has slightly ambiguous labels which are hard to match up

> with,

> tRCD, tRP and tRAS etc.

> http://www.techpowerup.com/articles/overclocking/64

> i.e Which one is which ?

>

> If I set bios to use SPD, Lavalys Everest "motherboard" ICH5 reports :-

> Memory Timings:

> CAS Latency (CL) 2T

> RAS To CAS Delay (tRCD) 2T

> RAS Precharge (tRP) 2T

> RAS Active Time (tRAS) 5T

> ???

>

> I've just set manually in bios:- (Below is how the bios memory setting

> options appear on screen btw),

> DRAM CAS# Latency 2.5

> DRAM RAS# Precharge 3

> DRAM RAS# to CAS# Delay 3

> DRAM Precharge Delay 5

> DRAM Burst Length 4

> ...and CPUZ reflects these settings accurately, ...(dunno what Lavalys

> Everest is doing ?!)

> anyhooo...

> ...completely confused, after reading lots about setting CAS to 2 can not

> be as "good" as setting it to 2.5 ???

>

> ...any advice much appreciated,

>

> TIA

>

> regards, Richard

>

>

>

>

>

>

>

>

>

>

[Guest Paul]

Re: OT: Memory expert please :-)

 

RJK wrote:

> I just bought 2x512 ddr400/pc2300 Corsair XMS 3200LL modules, and after

> doing quite a bit

> of Googling,

> I am no further forward in determing the "best" settings in bios, and

> indeed, my bios has slightly ambiguous labels which are hard to match up

> with,

> tRCD, tRP and tRAS etc.

> http://www.techpowerup.com/articles/overclocking/64

> i.e Which one is which ?

>

> If I set bios to use SPD, Lavalys Everest "motherboard" ICH5 reports :-

> Memory Timings:

> CAS Latency (CL) 2T

> RAS To CAS Delay (tRCD) 2T

> RAS Precharge (tRP) 2T

> RAS Active Time (tRAS) 5T

> ???

>

> I've just set manually in bios:- (Below is how the bios memory setting

> options appear on screen btw),

> DRAM CAS# Latency 2.5

> DRAM RAS# Precharge 3

> DRAM RAS# to CAS# Delay 3

> DRAM Precharge Delay 5

> DRAM Burst Length 4

> ...and CPUZ reflects these settings accurately, ...(dunno what Lavalys

> Everest is doing ?!)

> anyhooo...

> ...completely confused, after reading lots about setting CAS to 2 can not be

> as "good" as setting it to 2.5 ???

>

> ...any advice much appreciated,

>

> TIA

>

> regards, Richard

>

 

CAS affects the latency. Lower CAS is better. 2 is better than 2.5 .

 

Corsair products tend to have datasheets. If you look hard enough,

you can find the exact one for your RAM. I'm not sure whether this

is yours or not (need the full part number).

 

http://www.corsairmicro.com/_datasheets/twinx1024-3200ll.pdf

 

CPUZ from cpuid.com, displays two things. In the "SPD" tab, you

can see the values recorded in the SPD chip on the DIMM. That

may or may not reflect what the memory is actually capable of.

And will help you understand what the BIOS will do, when the

BIOS is set to use SPD. You compare the CPUZ SPD values to the

datasheet values, to see whether the SPD actually contains the

correct data. On some RAM, slower settings are used in the SPD,

to guarantee that the motherboard will POST - then the user

sets things manually, to the datasheet values.

 

The CPUZ "Memory" tab, shows the current choices for Tcl, Trcd, Trp, Tras.

So you can see what settings actually resulted.

 

When you see 2,3,2,5 in the datasheet, the order is "CAS Latency, tRCD, tRP, tRAS",

the same as in CPUZ.

 

I hope that answers your question.

 

Paul

[Guest RJK]

Re: Memory expert please :-)

 

Re: Memory expert please :-)

 

Many thanks :-)

 

regards, Richard

 

 

"R. McCarty" <PcEngWork-NoSpam_@mindspring.com> wrote in message

news:uUJCCqH0IHA.3680@TK2MSFTNGP05.phx.gbl...

> You may get more helpful info from the OverClockers forum:

> http://www.ocforums.com/ (Memory)

>

> "RJK" <nospam@hotmail.com> wrote in message

> news:eoxfBfH0IHA.4876@TK2MSFTNGP04.phx.gbl...

>>I just bought 2x512 ddr400/pc2300 Corsair XMS 3200LL modules, and after

>>doing quite a bit

>> of Googling,

>> I am no further forward in determing the "best" settings in bios, and

>> indeed, my bios has slightly ambiguous labels which are hard to match up

>> with,

>> tRCD, tRP and tRAS etc.

>> http://www.techpowerup.com/articles/overclocking/64

>> i.e Which one is which ?

>>

>> If I set bios to use SPD, Lavalys Everest "motherboard" ICH5 reports :-

>> Memory Timings:

>> CAS Latency (CL) 2T

>> RAS To CAS Delay (tRCD) 2T

>> RAS Precharge (tRP) 2T

>> RAS Active Time (tRAS) 5T

>> ???

>>

>> I've just set manually in bios:- (Below is how the bios memory setting

>> options appear on screen btw),

>> DRAM CAS# Latency 2.5

>> DRAM RAS# Precharge 3

>> DRAM RAS# to CAS# Delay 3

>> DRAM Precharge Delay 5

>> DRAM Burst Length 4

>> ...and CPUZ reflects these settings accurately, ...(dunno what Lavalys

>> Everest is doing ?!)

>> anyhooo...

>> ...completely confused, after reading lots about setting CAS to 2 can not

>> be as "good" as setting it to 2.5 ???

>>

>> ...any advice much appreciated,

>>

>> TIA

>>

>> regards, Richard

>>

>>

>>

>>

>>

>>

>>

>>

>>

>>

>

>

[Guest RJK]

Re: OT: Memory expert please :-)

 

Huge thanks,

 

....eventually noticed, in CPUZ that my i865PE based mobo/D935cpu | bios

"Auto" option was stubbornly setting FSB at 133mhz !!!,

....have now forced that to 200mhz in bios and CPUZ now reports fsb at

199.7mhz,

and fsb:dram ratio at 1:1 ...where it should have been - instead of 4:3 or

3:2 ...whatever it was,

etc, ....what fun ! ...in a minute or two I shall have a blue screen -

....I can feel it coming my way !

 

....do you think that I have matched up the labels correctly ? :-

i.e. am attempting to match CPUZ SPD info with my bios options,

...as below:-

tCL = DRAM CAS# Latency 2.0

tRP = DRAM RAS# Precharge 2

tRCD = DRAM RAS# to CAS# Delay 3

tRAS = DRAM Precharge Delay 6

 

? DRAM Burst Length 4

http://www.rambus.com/us/patents/innovations/detail/variable_burst.html

....now I have to choose between 4 and 8 !!!

 

regards, Richard

 

 

 

"Paul" <nospam@needed.com> wrote in message news:g38faq$nj3$1@aioe.org...

> RJK wrote:

>> I just bought 2x512 ddr400/pc2300 Corsair XMS 3200LL modules, and after

>> doing quite a bit

>> of Googling,

>> I am no further forward in determing the "best" settings in bios, and

>> indeed, my bios has slightly ambiguous labels which are hard to match up

>> with,

>> tRCD, tRP and tRAS etc.

>> http://www.techpowerup.com/articles/overclocking/64

>> i.e Which one is which ?

>>

>> If I set bios to use SPD, Lavalys Everest "motherboard" ICH5 reports :-

>> Memory Timings:

>> CAS Latency (CL) 2T

>> RAS To CAS Delay (tRCD) 2T

>> RAS Precharge (tRP) 2T

>> RAS Active Time (tRAS) 5T

>> ???

>>

>> I've just set manually in bios:- (Below is how the bios memory setting

>> options appear on screen btw),

>> DRAM CAS# Latency 2.5

>> DRAM RAS# Precharge 3

>> DRAM RAS# to CAS# Delay 3

>> DRAM Precharge Delay 5

>> DRAM Burst Length 4

>> ...and CPUZ reflects these settings accurately, ...(dunno what Lavalys

>> Everest is doing ?!)

>> anyhooo...

>> ...completely confused, after reading lots about setting CAS to 2 can not

>> be as "good" as setting it to 2.5 ???

>>

>> ...any advice much appreciated,

>>

>> TIA

>>

>> regards, Richard

>>

>

> CAS affects the latency. Lower CAS is better. 2 is better than 2.5 .

>

> Corsair products tend to have datasheets. If you look hard enough,

> you can find the exact one for your RAM. I'm not sure whether this

> is yours or not (need the full part number).

>

> http://www.corsairmicro.com/_datasheets/twinx1024-3200ll.pdf

>

> CPUZ from cpuid.com, displays two things. In the "SPD" tab, you

> can see the values recorded in the SPD chip on the DIMM. That

> may or may not reflect what the memory is actually capable of.

> And will help you understand what the BIOS will do, when the

> BIOS is set to use SPD. You compare the CPUZ SPD values to the

> datasheet values, to see whether the SPD actually contains the

> correct data. On some RAM, slower settings are used in the SPD,

> to guarantee that the motherboard will POST - then the user

> sets things manually, to the datasheet values.

>

> The CPUZ "Memory" tab, shows the current choices for Tcl, Trcd, Trp, Tras.

> So you can see what settings actually resulted.

>

> When you see 2,3,2,5 in the datasheet, the order is "CAS Latency, tRCD,

> tRP, tRAS",

> the same as in CPUZ.

>

> I hope that answers your question.

>

> Paul

[Guest RJK]

Re: Memory expert please :-)

 

Re: Memory expert please :-)

 

....though, I must say that, I've always been an "anti-overclocker," so I am

therefore a bit loath to raise my head above parapit in a "OC forum" !

....it's just that I've always been aware that higher performance memory was

available, and I have kept my "eye" on discussions across the years, i.e.

there appeared to be not a lot to be gained by paying a fortune for "higher

performance" memory modules.

However, seeing as my "old" Conroe i865pe has "older" ddr slots, with 2x512

Crucial CL3 pc3200 modules in it, and seeing as people are flogging on ebay,

their Geil and Corsair ...and Infineon CL2 ddr400 modules for a fraction of

what they cost new, I thought I'd buy a couple and see if I could notice an

improvement in performance.

 

....which was all a worthwhile, if only because whilst attempting to find the

correct manual settings for this "new" memory, I discovered, with the help

of CPUZ, and Paul (on this thread), that one of my stupid bios options was

causing cpu fsb to be set at 133mhz. How it ended up on "Auto" on the CPU

settings screen in bios, and how long it's been like that - I don't know.

i.e. I've kept an eye on those settings several times across the past year

or two, and to the best of my memory had never selected "Auto" !

 

....anyhoo, ...I "think" that I have finally selected the correct memory

timings !

 

regards, Richard

 

 

"RJK" <nospam@hotmail.com> wrote in message

news:eRBjQcI0IHA.5520@TK2MSFTNGP06.phx.gbl...

> Many thanks :-)

>

> regards, Richard

>

>

> "R. McCarty" <PcEngWork-NoSpam_@mindspring.com> wrote in message

> news:uUJCCqH0IHA.3680@TK2MSFTNGP05.phx.gbl...

>> You may get more helpful info from the OverClockers forum:

>> http://www.ocforums.com/ (Memory)

>>

>> "RJK" <nospam@hotmail.com> wrote in message

>> news:eoxfBfH0IHA.4876@TK2MSFTNGP04.phx.gbl...

>>>I just bought 2x512 ddr400/pc2300 Corsair XMS 3200LL modules, and after

>>>doing quite a bit

>>> of Googling,

>>> I am no further forward in determing the "best" settings in bios, and

>>> indeed, my bios has slightly ambiguous labels which are hard to match up

>>> with,

>>> tRCD, tRP and tRAS etc.

>>> http://www.techpowerup.com/articles/overclocking/64

>>> i.e Which one is which ?

>>>

>>> If I set bios to use SPD, Lavalys Everest "motherboard" ICH5 reports :-

>>> Memory Timings:

>>> CAS Latency (CL) 2T

>>> RAS To CAS Delay (tRCD) 2T

>>> RAS Precharge (tRP) 2T

>>> RAS Active Time (tRAS) 5T

>>> ???

>>>

>>> I've just set manually in bios:- (Below is how the bios memory setting

>>> options appear on screen btw),

>>> DRAM CAS# Latency 2.5

>>> DRAM RAS# Precharge 3

>>> DRAM RAS# to CAS# Delay 3

>>> DRAM Precharge Delay 5

>>> DRAM Burst Length 4

>>> ...and CPUZ reflects these settings accurately, ...(dunno what Lavalys

>>> Everest is doing ?!)

>>> anyhooo...

>>> ...completely confused, after reading lots about setting CAS to 2 can

>>> not be as "good" as setting it to 2.5 ???

>>>

>>> ...any advice much appreciated,

>>>

>>> TIA

>>>

>>> regards, Richard

>>>

>>>

>>>

>>>

>>>

>>>

>>>

>>>

>>>

>>>

>>

>>

>

>

[Guest Paul]

Re: OT: Memory expert please :-)

 

RJK wrote:

> Huge thanks,

>

> ...eventually noticed, in CPUZ that my i865PE based mobo/D935cpu | bios

> "Auto" option was stubbornly setting FSB at 133mhz !!!,

> ...have now forced that to 200mhz in bios and CPUZ now reports fsb at

> 199.7mhz,

> and fsb:dram ratio at 1:1 ...where it should have been - instead of 4:3 or

> 3:2 ...whatever it was,

> etc, ....what fun ! ...in a minute or two I shall have a blue screen -

> ...I can feel it coming my way !

>

> ...do you think that I have matched up the labels correctly ? :-

> i.e. am attempting to match CPUZ SPD info with my bios options,

> ..as below:-

> tCL = DRAM CAS# Latency 2.0

> tRP = DRAM RAS# Precharge 2

> tRCD = DRAM RAS# to CAS# Delay 3

> tRAS = DRAM Precharge Delay 6

>

> ? DRAM Burst Length 4

> http://www.rambus.com/us/patents/innovations/detail/variable_burst.html

> ...now I have to choose between 4 and 8 !!!

>

> regards, Richard

>

 

The numbers as presented, are consistent with a 2-3-2-6 RAM. The order of

appearance in the BIOS list, is not the same as the "standard" order

shown in advertisements and documentation. As long as you remember your

2-3-2-6 is Tcl, Trcd, Trp, Tras, you should be OK. So when looking

at the BIOS screen, you have to remember that they didn't put the

parameters in the standard order.

 

The "DRAM Burst Length" can be left at [Auto], as it makes no sense to

program it. As far as I know, the value "4" is used for dual channel

memory configurations. If the BIOS detects a dual channel configuration,

the BIOS should use the value 4. If the BIOS detects a single channel

memory configuration, then it should use the value of 8. I think the

idea is, the total amount of data taken from the memory ("4" x 16 bytes

or "8" x 8 bytes), should match the cache line size of the processor.

I don't play with that setting, and leave it at Auto, because the

BIOS is more clever than I am :-)

 

Paul