Hi all. I built my own system about two years ago and it was working fine for a long time. One morning in the beginning of September, after a thunderstorm , the machine would not boot past the BIOS. I had made no software changes or hardware changes to it before i shut it down that night. Sometimes it wouldn't even load the BIOS, it would power on and three of the red lights on the back of my HD 4890 would stay lit up.
So I did some tests and ran Memtest86+ and found that the RAM was full of errors. I RMA'd the RAM and got it back, plugged it into the mobo and the machine worked well for a few hours and then I had the same problem of not being able to load Vista after the BIOS, sometimes not even being able to load the BIOS.
So I thought the mobo was the reason that the RAM failed Memtest86+ tests. I bought a new motherboard (M4A79 Deluxe) hoping that would fix the problem. I swapped all of my components into the new mobo, booted up, wiped my hd and re-installed vista. Once vista was installed, I would get random blue screens once vista had loaded my desktop and the system would restart.
I set my cpu to run at 2.0Ghz (200X10) to see if there was a timing error. This stopped the random blue screens. I updated the bios on the m4a79 deluxe to the newest version to see if i could run the cpu at the stock 2.6Ghz (200X13). Now the system won't load Vista at all. It will load the BIOS, sometimes, and then when trying to load Vista it will hang, those 3 lights on the back of the HD 4890 stay red again, and the computer won't boot again unless I clear the CMOS. After I clear the CMOS, I'll get the BIOS but Vista won't load. A few times even the BIOS wouldn't load, it would boot past the Asus intro screen but would display the AMI screen with jumbled, distorted text that you couldn't even read. So i let the rig sit for one day, tried to boot it with just the video card connected and the bios loaded. So i hooked up the HD, loaded through the BIOS and when trying to load Vista the system hung and the 3 lights came on the HD 4890.
I know that the GPU, HD and power supply are working fine because I was able to test them on my socket 939 system. But since it's a 939 board I can't test the RAM or the CPU on it. I just got the RAM RMA'd, so that shouldn't be an issue. The CPU is my next guess but I don't get why it will load Vista sometimes and not others.
I am at a loss. I think perhaps the CPU is malfunctioning but I don't get why it would load Vista a few times, and then not. I was able to use Vista for about two hours after I got the M4A79 deluxe up and running, so the CPU is not totally fried, but I'm not totally convinced it's working correctly either. Will a malfunctioning CPU be able to work sometimes and not others? I really want to get my rig up and running again but I don't want to keep buying components without knowing if it will help the situation or not.
Any and all input would be greatly appreciated. Thanks so much for reading this post.
Windows Vista Ultimate 64-bit
Asus M4A79 Deluxe (replaced M3A79-T Deluxe)
AMD Phenom X4 9950 Black Edition, 2.6Ghz, Stock Cooling
4 GB (2X2Gb sticks) OCZ DDR2 PC2-8500 1066Mhz Platinum Series
Saphire ATI Radeon HD 4890
LG 22X DVD+-R DVD Burner SATA
Seagate Barracuda 7200.10 500GB 7200 RPM 16MB Cache 3.0Gb/s
TX750W power supply
Antec 900 Case
Asus VW246H 24" 2ms HDMI Widescreen LCD Monitor
I adjusted the memory specs in the BIOS. I reinstalled Vista and now everything seems to be working fine. Except for the fact that I can't get my CPU to run at the stock 2.6Ghz. (200x13). I can only get the rig stable at 2.0Ghz (200x10). If I increase the multiplier or the FSB, it crashes. I've been using voltages between 1.25-1.28 volts. Any thoughts?