Computer shuts off during boot

[skoolie1]

I built this computer for my wife back in July 2007.
Specs: WinXP SP2, Abit NF-M2S, AMD Athlon 64 X2 3800+ 2.0GHz, Wintec 1GB RAM, WD 80GB HDD, onboard video and LAN, floppy and DVD drive. The power supply is a CoolMax CM-300.

The computer started to crash randomly about a month ago and has gotten worse. Now it dies during boot up. I ran MemTest and the RAM was failing. I bought new Crucial RAM - 2GB. I ran MemTest for 2 hours about 3 passes and no errors. The problem still exists. I can get to Safe Mode command prompt. I ran msconfig and selected the diagnostic boot up. No drivers or anything is loaded. Normal boot up it fails. On the screen I get the XP splash and a few runs of dots then click. It's off. I took out the hard drive and put it in my other machine. I ran scan disk and found no errors. I can read all the data with no issues. I bought a new hard drive and started Setup. It runs about half way and then click. It's off. I took a power supply out of another working PC and the problem still exists. I shorted the BIOS pins and reset the BIOS. I booted and loaded defaults. Problem still exists. Boots up half way and then click. It's off.

Is my problem the motherboard or CPU or both? or???

 

[CuDobh]

Have similar problem with a Fujitsu-Siemens Scaleo 800 S. Disks seem to be OK.. Memory at first was giving MemTestx86 the hickups but after I reseated all of the modules it comes out OK...

Problem is that even booting Live-Cd systems like Knoppix, HawkesPE etc. fails...

PSU delivers correct voltages.. CPU have been tested in other computer and is OK..

BIOS reset and reflashed...

Smells like a motherboard-failure but I am not that convinced..


CPU is old P IV @ 3.0 GHZ
RAM 3GB DDR
HDD: WD2500JB (Western Digital 250GB) +ST3320620A (Seagate 320 GB) all IDE.

CHKDSK reports nothing and S.M.A.R.T is ok for both.

 

[skoolie1]

I changed the motherboard and rebuilt it to fix the issue.

 

[CuDobh]

What I was afraid to hear.. Will be hunting for a newer PC.. Just have to win the lottery first

 

[tookthebluepill]

Skoolie1 - where did you find the replacement board? I have the same problems on an 800S machine (and tried exchanging everything except the motherboard). This is an old post so I suppose that even if you gave me a tip, the place that you got it from probably won't carry it anymore. But it's worth a try.