PC won't start from cold

[Cheerful Dragon]

For some months, I left my PC on 24/7. September last year, I found the PC wouldn't start from cold. I thought it was a glitch, but had the same problem at Christmas, so obviously not a glitch. The symptoms are these:

Switch on PC. Monitor stays blank. No lights to show any drives being accessed. Not getting as far as BIOS, by the looks of things. I can hear the system fan going, but that's about it. After a few minutes warming up, CD drive lights flicker. At this point I power down, wait a few seconds, then switch on again. I have to repeat this a few times to get the PC to start. Once I've got the PC to start, everything seems fine.

Things tried:
Vacuuming inside of PC - no effect
Ensuring cards and RAM are correctly seated (cleaned edge connectors) and all cables are firmly attached - no effect
Replaced battery on mobo - no effect (*more on that later)
Tested RAM - tests out OK

*I replaced the mobo battery for two reasons. Firstly, somebody said it might be causing my problem; secondly, the PC clock lost time while the PC was off. When I turned the PC off recently, I found the clock was still losing time - 43 hours over 10 days (the calendar is now 1 day out).

PC Spec: AMD Athlon 1.2 GHz CPU, Chaintech CT-7AJA mobo, 128Mb RAM, SoundBlaster 5.1 Live soundcard, nVidia GeForce2 graphics card, 40Gb hard drive

I have not added or changed any hardware since the problem occurred, nor did I add or change anything immediately before the problem occurred. I don't have access to a second PC so I can try swapping things to try to find the problem. I can't afford to take the PC to a repair shop, which is why I'm here - free advice! That also means I need an answer that doesn't involve replacing bits 'on spec.' to see if that fixes the problem.

Please help!

 

[RealBlackStuff]

All symptoms point to a dying powersupply. Check all the voltages in your BIOS or get the free Everest Home program from www.lavalys.com
If the voltages shown are within max. 5% (under or over) of their nominal values, your PSU is still OK.
Report back with results please.

 

[Cheerful Dragon]

Results from EVEREST report:

Sensor

Voltage Values:
CPU Core 1.73 V
+2.5 V 0.23 V
+3.3 V 3.28 V
+5 V 5.08 V
+12 V 12.23 V
Debug Info V 86 C2 9F 91 13 CE CD CC

Don't know what the CPU Core value should be, but the +2.5V is way out!

I also spotted this under memory:

Physical Memory:
Total 127 MB
Used 122 MB
Free 4 MB
Utilization 96 %

I'd recently rebooted my PC and the only things running were Everest and Notepad. I started IE and rechecked. Memory usage went up to 124MB - 98%! What is using up so much memory and how can I fix it?

 

[Cheerful Dragon]

On running msconfig.exe, I found loads of unnecessary stuff being run on startup. I removed the things I know I don't need. Memory usage dropped to 76% It still goes up to 98% when I go on to the Internet, though. :-(