Mr Carrington kindly helped me out on this one. Last night I got home and my PC was on but dead to the world. So after his advice I switched it off reseated the RAM and some other bits and it came live again. Used it last night and left it folding, and this morning it had done the same thing. Symptoms are no signal to monitor or keyboard, and when rebooting it gets to the windows XP screen with the scrolling bit, does that 3 times, slows, lights on keyboard, bang, gone! I have a feeling it could be an overheating issue so going to look into extra fans and check existing fans do work (they were spinning when I opened it up last night) I forgot to say it boots up fine in safe mode whenever. But will not boot in networking safe mode or normal.

I reckon it will boot up fine when I get home, with it having been turned off during the day. Maybe I'll leave speedfan and CPU-Z running during the evening to monitor things.

Any ideas folks? Its some form of cut out - limp mode thing. Just need to find the trigger.

Did you see a lot of dust and fluff? Sometimes a good hoovering can have an amazing effect on temperature.

If you have no fan other than the one in the PSU, it could well be temperature related if you are using the machine 100% of the time for folding.

Sure it's not just the PSU - these fail a LOT more on me than CPU fans tbh.

Power supply on it's last legs gets my vote

Take the case off and try it - if it still goes off it isn't temp.

You may have a duff connection that becomes apparent when it's warm - mine does it. Take everything out of the motherboard and reseat everything.

A pencil eraser across the gold connectors on pci cards etc works wonders if they're a bit mucky.

Have you been tinkering, Jason ? Perhaps there is some straw in there?

Epson USB connected printers somehow play a big part in these problems, I've been tracking a similar problem for months on an HP XP machine. Serial modems are also a cause.

Shut down

Disconnect USB devices

Switch on and it'll work

Then reconnect the USB devices (most support hot-swapping so you'll have no problems once booted)

Maybe search for some updated onboard USB hub drivers.

HTH

Sam

This can indeed happen - it's why I've started using powered USB2 hubs at work, as my laptop cant drive all this USB2 powered gear

Well, after persistent random cutting outs I removed the 360w PSU and replaced with a 300w PSU that was relatively new in another PC tower I have lying around here as "spares" - seems better now.

sounds like a PSU thing to me too - my old machine was doing the same just before the PSU burnt out!

Replaced it with a 500w one now so hopefully it won't happen again

You may remember I had a similar problem not too lonag ago J, it was the PSU in my case too.

One thing to always bear in mind - a PSU may be 500W but that's probably peak/max power. Look at the continuous load it can handle, and knock that figure down by about 30% if you don't aircon your room

Most of these PSUs are rated for 20 or 25 degrees C for the power stated. So when it's hotter the actual power rating can be way lower.

Also a 300W quality PSU (server class) will generally be vastly superiour over a 500W no-name 20 quid PSU. Weight tends to give it away with PSUs, to some extent.

That said there are non-A-brand PSUs out there which are excellent

Right,this 300w PSU is also causing the PC to cut out as soon as I try and use the CD-ROM drive (either of them) so I'm guessing its coping fine with the load as normal but killing power when demanded. I'm going to have to look into a decent one I feel. Might see what PSU is in my "other" spares repairs tower.

PSU's are the pretty poor in most desktop systems you buy off the shelf these days and will usually give in. All built to a budget, so good enough, but not great.

If you can afford it i use tagan supplies, but they are not cheap. Enermax used to be good, but we noticed a lot tripping. If you post or PM a spec can certainly get back with a what you require if you need any info

From what you have said the old one was on it's way out and not producing clean power, hence cutting out. The new one just can't provide the juice needed.

Indeed - Enermax is one of those companies that produces good PSUs but rated at 20 degrees C (IIRC) - so I tend to end up overspeccing as it needs to run in a fairly heated loft

Indeed - Enermax is one of those companies that produces good PSUs but rated at 20 degrees C (IIRC) - so I tend to end up overspeccing as it needs to run in a fairly heated loft

Have a look at the tagans, the power rating they gave on my PSU is what it can deliver 24/7, which was nice