For a little while now it has been restarting when I leave it idle for a bit, but today it went off suddenly while I was using it. More importantly, it didn't restart, and wouldn't start up even when I turned the power on and off. The mobo didn't even beep; only thing I could hear going other than the fans was the DVD drive turning over once.
So I started detaching components one by one, and once I had both sticks of RAM removed, the mobo beeped liked crazy to tell me I had no memory. Once I put one stick back in, nothing happened. I switched to the other in the same DIMM slot, and that did it. The screen came up with "The previous performance of overclocking had failed. The system is restored to the default settings. Press any key except Del to enter setup." Now I don't overclock, except that I have ATI overdrive function that comes with my GPU drivers switched on to manual fan control for my GPU fan control (because if I leave it automatic the fan stays off until it heats up and then comes on super loud for a couple of seconds and scares the crap out of me). So overclocking is not the problem, though I do seem to remember seeing this screen the last time I was having computer troubles some months back.
From there things progressed OK. The system booted up and things seemed fine. Having no energy at that time to write this post like I knew I should, I kept computing... until several hours later it happened again. To abbreviate a little, I experimented with much removing of hardware, but it was mostly the RAM that did it. As with the first time, I got the computer to start up by basically taking the RAM out and putting it back in, except that this time I could only get it to work with one stick at a time. Worked with either stick, and in either of the first 2 DIMMs. But it's also temperamental; it seems to want things changed around every now and then just to reset the system somehow. Each time I got it to work, I would turn it off and try adding the other stick of RAM again to get full function, and when that failed, I would take the second stick out to return to the previous working configuration, and it would fail. Until I moved the sticks around a few times, and then it would decide to work again. And remember, when it fails, the mobo makes no beeping at all and there is no signal to the screen.
I did get it to work a couple of times with both sticks of RAM, up until the point of getting an image and the "Overclocking failed..." message, but at that point when I tried to press a key to continue nothing happened.
Like eight months back my system died and I took it in to get diagnosed and was told it was the Mobo, so I bought a new one and it still didn't work so I took it back and they said "Oh sorry, no actually it's the GPU." So I got a new one of those too. So the GPU and Mobo are fairly new and most likely not to blame. Here are my components:
ATI Radeon HD 4870
K9 A2 CF mobo if I recall correctly Model (MS 7388)
1Gb currently of 2Gb of Corsair 6400C4 XMS2 RAM
Antec True Power Trio 650 (Possibly the 550, but I think it's the 650.)
WDC WD2500AAJS-00RYA0 Sata Harddisk 250 GB
LITE-ON DVDRW LH-20A1P ATA DVD drive
Vista 32bit Home premium.
My uneducated intuition wants to blame the PSU, as it is outdated for the system now that I have the powerful new GPU. And people are always saying the PSU is the first thing to fail and can cause all sorts of problems. I just hope if the PSU is to blame it hasn't all ready messed up the rest of my hardware.
As I alluded to earlier, there is only one computer repair place in town and they're not very competant, so it would be great if I could get some advice here about how to diagnose the problem myself.
Please help. How do I find out what is to blame?
Thanks in advance.