Black screen and flashing underscore after reboot

[Hengest]

Hi,

 

I have seen other threads with a similar title but all sem to have occured after the poster did something.

 

By PC just rebooted itself while I was working and after the POST went to a black screen with a flashing underscore. I tried rebooting but got the same thing, never getting to the windows loading screen.

 

System details are:

 

Windows XP Home SP3

Dual core Pentium 3.2Ghz

Asrock 4Core Dual VSTA Mobo

2 Gb OCZ Ram DDR2 (2 x 1Gb)

160 Gb Maxtor IDE drive

Sapphire ATI Radeon X1650 PRO PCIE Graphics card

 

On booting I get the POST screen and short beep as normal. I have done some things already so maybe I should list what has been done:

 

Removed all peripherals, USB etc.

Removed each stick of Ram

Swapped IDE cable

Removed HDD and tried as slave in another machine, works fine.

Tested all PSU outputs, under load, with Fluke meter (all fine but grey wire showed 4.7v, is that low and would it matter?)

 

Last week I had a malware issue which I worked through with a helper at Malwarebytes and everything was ok after that but I am wondering if this could actually be a software issue related to that problem.

 

The thread at Malwarebytes is here if it helps:

No explorer or admin permission after Microsoft Security Essentials Alert - Malwarebytes Forum

 

I look forward to hearing from anyone who may be able to help.

 

Thank you.

[Pixelkitten]

This sounds pretty weird IMO. Have you tried waiting it out? Usually this happens when a loading file is corrupt or otherwise broken, missing etc.

Try waiting, say, 10min? If nothing happens, I suggest a repair/reinstall.

[Hengest]

Hi, yes I tried waiting it out. Left it for an hour but the screen just stayed black with the flashing underscore.

 

I was thinking that it could be a corrupt file but don't see wh that would have just caused the PC to shut down.

 

Thanks

[Jelly Bean]

The first thing I would do is enter BIOS and check all your hardware shows such as your hard drive....

 

 

Ok have you tried rebooting and repeatedly tapping F8 key and choose last known good config or safe mode?

 

Do either of these work?

[Dalo Harkin]

The flashing underscore means that the PC is searching for something, but there is nothing there.

 

As has been suggested you need to check in the BIOS to see if the HDD is visible and if it is that it is in the BOOT list.

 

Its most common when the CMOS is reset and you dont have a floppy drive installed, but the floppy options are not disabled in the BIOS :)

[Hengest]

Yes all drives show up in the BIOS.

 

I tried doing a repair install/recovery but my XP disk does not give the repair/recovery console options when booting from the disk. Apparently that is a feature of disks from some suppliers.

 

I am feeling quite sure now with all of the tests I have done that this is going to be a software problem rather than hardware.

 

In the absence of the recovery option I am thinking I will have to get a new HDD, do a clean install and then fit my old drive as a slave and transfer files over.

 

Unless there are any other suggestions?

 

Thank you :)

[Pixelkitten]

Sounds like a good idea, unless it IS a harware problem and you end up ruining everything, like me.

[Dalo Harkin]

You say that they show, but is the HDD (with the OS on) at the top of the boot list?