Dell Optiplex 745 crashes on dual core only

I picked up a couple Dell Optiplex 745's that are almost identical. A friend of mine has the same machine that runs Windows 7 flawlessly. I, however, can only install it and run the OS when disabling one core of my Pentium D 2.8GHz (Presler) CPU. When I go into the BIOS and re-enable the 2nd core the system becomes completely unstable.

Some basics:

x86 (32-bit)- Windows Home Premium retail (Came from Dell with XP)

System close to four years old, with format and clean install of Windows 7. Machine does run OK on Windows XP with both cores enabled. Both machines seem to perform exactly the same so bad CPU or memory seems to be a longshot.

Zip file attached. Thanks for any help!

Eric

You uploaded the wrong file, the .EXE file was uploaded not the .ZIP file

Right you are - thanks for the heads up! I have corrected the zip file in the original message.

Regards,
Eric

Update your Networking drivers in safe mode with networking
Dell does not provide any drivers for Windows 7 and most of their drivers are dated from 2007
Install the Broadcom driver in http://www.sevenforums.com/tutorials/316-compatibility-mode.html

Go to this page and choose Vista 32-bit

View attachment 132992

OK. Gave it a shot. Had two BSOD within 30 seconds of logging into windows. Zip file attached includes tonight's dumps.

Another odd thing is whenever I enable the 2nd core my ESET antivirus goes all funky and won't operate. Don't know if this helps narrow it down or not. However, these BSOD's occurred on a clean Windows install before I even added a single non-Windows program so I know the anti-virus is not the cause.

Thanks,
Eric

More updates:

1. The machine started getting unstable even when only running one core.
2. I have run the Dell utilities and find that the machine will fail immediately on dual core when running the "thrash" test on the cache.
3. I have run Memtest again and I am getting failures when running single or dual core. I have tried three different simms (one at a time) and they all fail similarly.

I have a hard time believing that all the simms are bad. It sounds like a processor or other hardware problem to me. Any way for me to further diagnose this?

Thanks,
Eric

RESOLVED!!!

I replaced a suspicious looking 1800 uF capacitor close to the processor and all is well. All memory works, all programs work, and has been completely stable for the last 6 hours.

Thanks to yowanvista for responding and hopefully this thread helps someone else.

Eric

emp1172 said:

Thanks to yowanvista for responding and hopefully this thread helps someone else.
Eric

Click to expand...

Yes, sir! Thanks, Eric, you've saved my time... I have exact situation as you (including damn burned 6.3v 1800uf capacitor close to CPU (shame on engineers designed that mobo!).
Ordered couple of capacitors on ebay yesterday; will report progress on arrive (I hope it will work for me).