I must add that I am not impressed with PB's support site setup-- either !!
You can sort to your specific board... but if you try to go to troubleshooting advice-- they cover ALL PB's products. Needle-in-a-haystack philosophy of tech-support.
If we make it too hard to find they'll stop bugging us LOL.

The PSU is a stock item. It is rated as follows:

+3.3V & +5V = 151W max, total output continuous shall not exceed 250W max.

This sounds a little weak considering I have seen 400W (I think) PSU out there.

I have looked at all the connections, and even disconnected the graphics card (ran on mobo VGA adaptor), DVD ROM, and spare drive. Leaving just mobo, CPU fan, SATA drive. Still no change.

I used to work on classics (VWs) so am well used to sorting out other peoples work on the electrics, "what's going on here??" type questions. The wiring diags were generally useless as looms had been modded beyond that what you could call standard.

I think I'll resign to the fact that a new mobo is in order. Perhase one that can take 4 DIMMS so I can expand the memory further. I'm on a AMD sempron 3000+ at the moment. Not lightning quick, but ok for general stuff and the odd game. I don't want to spend a fortune on a high end machine (I have a 360 for that) but one that can handle vista ultimate with ease. This is why I upgraded in the first place (memory, graphics card and SATA drive).

Can you reccomend a mobo that will allow a 4Gb memory upgrade and take my AMD Sempron? I'll maybe upgrade the CPU later, but I think it needs a Socket 754 or something. I think AMD Athlons are 754's, which I suppsoe would be a good upgrade.

I may have another PSU somewhere from an old build I did when XP first came out. I'll check the rating on that.

Yeah PB are crappy for that kind of thing. I remember years ago I got a PB 486 DX2-66 from them (that was a LONG time ago), and I recall having nightmares upgrading that too. I did promise never to buy PB again, until 18 months ago - should have stuck to my guns eh??

I look forward to hearing your suggestions.

Cheers - as always.

Oops, should have read 115V Watt max on the PSU spec (not 151W).

I would have to research the mobo... you have different voltages over there--
to get a rough idea what you requre for a PSU-- I would upgrade that FIRST... 250 W is very small for a modern board/CPU. That could be the source of all this...

Enter your mobo Socket 754
enter your CPU/RAMtype (use DDR-- double-sided)
all your peripherals/printer/EVERYTHING

eXtreme Power Supply Calculator Lite v2.5

click on calculate-- it will give you a number of watts-- this is not the only consideration-- but it's a guideline. I would add about 100W to that total for future upgrades-- and that's where you start looking. Too high is better than too low.
there are also vast differences in quality-- I will suggest some trusted brands ...maybe help you look for the best deal.

I must go to work in a bit-- but I will check in-- let me know what the calc says OK?

That's great.. It came up with 218W. I have nothing special:

AMD Sempron 3000+
2 Sticks of DDR (2Gb)
GeForce 7600GS
1 DVD Writer (All formats)
1 SATA drive
1 IDE 7200rpm drive
I'm sure there's a fan controller on there too...
Printer has own PSU

The rest is stock.

So I'd say a 350W to be safe??

Speak later I hope.

That's your INput voltage-- you need to know wattage of output-- usuall on label on side of PSU... inside the case.