Won't boot - unknown cause

[burberryjam]

Hi,

Currently I cannot boot. My hard drives are not even detected, and my AGP card is shaky at best. Hopefully anyone who knows anything can offer some advice?

First off, my rig:
Jetway V2DP KM266 Pro with VIA 8235
Sempron 2400+ socket A
768mb pc2700 samsung ram
2x IDE hdd
1x Cd RW
1x safecom wireless NIC with realtek chipset
old gfx card: radeon 8500 64mb
new gfx card: PNY Verto 6600GT

Now, the problem

When I first inserted the new gfx card, it was detected ok. Restarted and it was no longer detected. I assumed this was just me not seating it correctly in the slot, as it would work once then not later. Now after installing it properly with drivers, and rebooting as required, I can no longer boot and cannot access BIOS. It just hangs on the first screen. It might detect the RAM, it might not. But now it always fails to even detect my IDE drives, it wont even print that it is detecting IDE drives.
Resetting the CMOS and removing the AGP card gives no luck. Still no detection. Have tried plugging in only one hard drive, resetting CMOS and running off internal graphics, but still no luck.

I have my worries about my PSU, as it seems to be very, very crappy, wouldn't be surprised if it was a deer tbh... before any problems, it would emit a high pitched whine after shutdown (not the fan) which would go if i turned off at mains; it would sometimes give me a shock if i touched the case near the PSU. Now, it makes several different pitch whines both when plugging in and turning off... I believe it may be failing.

I want to go through each piece of hardware and test it to see which is causing me problems, but I am worried my PSU might suddenly zap and fry any connected equipment.

I have reason to believe I have overloaded it and this has caused the problem as my new gfx card took a molex connector (took it out of cd drive and put it in gfx card - uses way more power right?) and this is the cause of the problem, but am not sure.

I have waffled as usual, but that is my situation, any advice?

Oh, and I am worried that it could be cause I tried to overclock my cpu from 166fsb to 180 and then tried to oc my radeon, but then again I didnt fiddle with the voltages at all so doesnt seem likely?

[Pob255]

Could be motherboard has had enough, off hand more likely the PSU, if it is the PSU then without a new one there's no test you can do on any of the other hardware because it's all dependent on the PSU.
Sticking the 6600gt in there was probably the straw that broke the deer's back

Deer psu, that's a name I'm greatful not to of heard in a long time

Hightpitched whine after shutdown, my guess one of the capasitors has blown.

All told, I think the best option is a new pc or a (new to you) 2nd hand one.

[burberryjam]

Oops, i've since gone about it methodically, and now found that the new gfx card is most likely the culprit, either its bad or it doesn't get enough power from my lacklustre psu: everything works smooth as silk if that card isnt in my case, but the second it's in, I dont POST, no beeps - no single beep to confirm POST; no long, slow beeps to let me know theres no RAM after I yanked it all out, nothing. However, hard drives spin up, cd drive opens, cpu fan, psu fan, even new gpu fan all spin, but it won't post! Im guessing this means that either a) gfx card bad or b)psu too low-wattage to power it all. Not too sure about b) as it wont POST even if i remove all components and just power on the gfx card. Its not the AGP slot as my old card works fine.

Thing is, the new card definitely worked before as it used to come up onscreen before any post screen and all would be well, could even boot into windows! I always ground myself before touching and keep it in anti static bag when switching out. Quite confusing! Any thoughts?

Oh and the psu is still whining, im just too impatient to buy a new one. Is there a (safe) way to identify it 100%? Here is all the info I can glean from the case:

Model: LC-B300ATX
ROP: 041201-81-LC
Then a big table:
// 115/230V~ // 8/4A // 60/50Hz //
// +3.3v / +5v // +12v / -12v // -5v / +5vSB //
// 28A / 30A // 15A / 0.8A // 0.3A / 2A //

Then some guidelines which annoy me:
+5v & +3.3v combined 180W
+5v & +3.3v & +12v combined 280W
Total 300W MAX

then a small bit at bottom saying SW30XA.

It has one 20pin ATX connector, a P4, 4 x Molex, 1 x FDD.

Even more info for those who got this far...
Its an 8x AGP card, my mobo supports 4x, but in the manual supplied on card CD it says it supports agp 2.0 or agp 3.0 so this is probably not an issue?

I did manage to load windows with the card once before, it was recognised with HWinfo as the correct card and it did load graphics. it all went shot after I installed the drivers. The only thing I can now think of is that the PSU is losing power fast and no longer supports the requirements, although the fan still spins. Is this plausible?

[burberryjam]

Ok im just going to buy a new PSU, what do you think of this one? Its 24pin so will work in a new build, and AFAIK I can use it to power my 20 pin mobo, what do you think?

http://www.scan.co.uk/Products/500W-...12V-PSU-ATX-22

[K3V]

also check the capacitors on your motherboard, jetway's have a habit of leaking