first build instabililty

[maomatt]

I completed a first build a few weeks ago and had no problems initially, once I got XP Pro installed.

specs
Antec TRUEPOWERII TPII-550 ATX12V 550W Power Supply
BIOSTAR TForce4SLI Socket 939 NVIDIA nForce4 SLI ATX AMD
AMD Athlon 64 X2 4400+ Toledo Dual Core Processor Model ADA4400CDBOX
2 X Western Digital 320GB 7200 RPM SATA 3.0Gb/s
Western Digital 80GB 7200 RPM IDE (drive from old machine)
NEC Black IDE/ATAPI 16X DVD±R DVD Burner Model ND-3550A - OEM
SONY 1.44MB 3.5" OEM
2 X XFX GeForce 7900 GT / 256MB in SLI
2 Gig Memory Kingston ValueRAM 1GB 184-Pin DDR SDRAM DDR 400 (PC 3200)
Antec Performance I P180 case
this is intended to be a gaming/number crunching rig for work and play.

The machine ran fine at first, but after a short time began to behave erratically; locking up on XP longin or after being idle for a while. Thinking that I might be drawing to much power, I disconnected the non-boot drive and the system ran fine; so i added one drive back. It then locked up after being idle. SO I swapped in the other drive. And it locked up again. So I ran it with jus the boot drive. And it locked up.
After lockups strange things occur:
* I attempts to boot to an old Windows 2000 partition on the 80 GB drive, despite that drive being last in the boot order in bios
* Freezes at the DMI Verification screen. Rebooting again or unplugging power to one of the auxilary drives usually corrects this problem
* NON SYSTEM DISK error until I insert my XP Pro disk, run repair, and tell it which drive is the boot drive
* ad nauseum

The HDDs all passed extended WD diagnostic tests. The memory passed Memtest+ with no errors as well. The computer did, however, lock up once during memtest. Only one HDD was powered up during Memtest.
But
I ran 3DMark06 the other day, just to get a feel for how fast the graphics were. Nothing spectacular, but I DID notice that only ONE logical CPU showed up in the system info. I compared this to other AMD dual core machine and they all had two logical CPUs. Also, in task manager only one CPU usage history window appears. I dont know if dual core chips would show 2, but I assumed they would. Is it possible I have a bad CPU?
Any suggestions?

thanks

 

[fire400]

take everything out of the system, rewire everything again

load the motherboard with minimums,
cdrom, video card, keyboard, mouse, 1 stick of RAM (or in whatever order you chose to do it in)

next, add a peice of hardware one by one and find out what the problem is

if you feel your OS is the problem, reinstall the OS after you erase and fully erase the hard drive, do not do a repair or quick initialization

something has to be faulty, once you've found out it's hardware or software, that pretty much renders where you want to put more of your time into, diagnostics first

p.s. get your warranties reeady, stuff like that happens. to me, it sounds like your OS isn't being friendly right now, but it could be anything

 

[maomatt]

Found a partial solution. The single logical CPU was due to not selecting "ACPI Multiprocessor CPU" at Windows XP Installation. I did a low level re-format and reinstal and that issue is fine now
But I still have lockups.
The power supply voltages are within 5%, but are "jumpy" They vary a percent or so even when machine is idleing. Can that be an issue?