I've got a fairly old PC (6years?), never a problem once up and running, but it is getting increasingly difficult to start up.

At any point during the boot it can just switch off like the plug was pulled. Sometimes fine, other times it takes 3 or 4 goes. It refuses to have another go until the main power button is left off for 10sec or so. Is this symptomatic - any ideas? :confused:

Have you got any more details on the spec of the machine?

maybe a weak power supply? or possibly a faulty motherboard (if its a athlon it could be thermal shutdown)

Check the motherboard for any leaking capacitors.

If they are there then the board can be repaired by somebody who can get the caps and solder them on, but tbh you are better off binning it and starting again when it is that old.

Thanks, cheezemonkhai, I know I should bin it really.

It's an Evesham supplied AMD Duron?/Athlon 700MHz/K7 Pro ATX IR3 Mother/128Mb/Win98 - 100% reliable, hard disk perfect etc., but 6th birthday imminent.

Interesting you mention the thermal shutdown as it started with the hot weather but it's cooler now???

Boards or that era had a lot of a bad batch of caps, definately have a look and see whats what as if it's just a PSU you can get a new one for peanuts.

If the caps are gone then it is new system time, an di have seen many systems of this era show that problem. Pay particular attention to the ones in the VRM

Oh and hard disks are 100% reliable, right until they fail

I think I'll just bite the bullet and call it a day, I've had good value out of it. I hear you on the hard disk, I've had this nagging voice telling me to back up all the important stuff recently!

Cheers anyway.

For info:

I installed 'Everest' temporarily and it gave steady & correct power supply voltage readings, so PSU probably OK.

I opened up the case and 3 out of 4 of the capacitors on one board of one colour (make/rating) were badly bulged and at least one had clearly leaked/crusted. Likely as not this is my problem. There are plenty of pictures on the web of failing caps.

It is gradually taking more and more goes to boot up, and 'switching off' sooner and sooner after power up each time. Once it makes it as far as Windows screen it still seems stable though, and is fine if left on all day (for now!).

RIP :(

it might be the psu (Power Supply Unit), that was the problem when it happened to me, goodluck

Are they the black caps with the X on the top or the green ones with the K that are failing. If you can solder well enough you should still be able to get replacement parts which will make your board happy again for pennies (Think I got 5 of them for about 70p). You should change all of the type that have popped.

I've seen so many of these and they do cause exactly the behaviour you say.

If not I always found Mesh really good for PC's for home.

cheezemonkhai,

Yes it's most of the black X ones (some look like the X is about to burst). Today it took over a dozen power on/off cycles to boot, then for the first time failed to load windows repeatedly. I haven't got much I need (& nothing vital) on it so I've put what I want on my ISP webspace for backup. Hence why I'm up at this hour.

I was reading a guide on replacing the caps (even found one person with my exact board) so I'll have a go as it doesn't really matter if I mess it up. Obviously the replacements have to be a similar size and rating, but do they have to be a particular grade? Can you point me to something suitable (on Maplin etc.). Thanks again.

Look at RS, is where I pick my spares up but you might find them a bit hard to get.

I would find the one you currently have but pick a different brand of cap. Make sure the valtage is the same or only slightly higher and make sure that the capacitance isn't any lower than the current ones.

Maplin might have some but i wouldn't be sure. IIRC i think they are usually 6.3v 1600uF ones that die, but do double check.

Thanks cheezemonkhai, I'll have a closer look.

I'll let you know how I get on.

(Left PC on standby all night & OK, but going to have to turn off later, I suspect this may be my last post for a while!)

I changed some of these caps a little while ago for someone for the the same problem. Got them from Farnell Electronics online. Cheap as chips. I tend to find that they have a good range of components.

biomulv, re. Farnell Electronics, just too late, but thanks anyway, looks very useful and no doubt I'll use in the future.

PC still alive. All the black/gold I.Q. make caps are bad, 2 different ratings 6.3V 1600uF & 10V 2200uF - ordered exact matches by panasonic from RS. Only a few quid all in. Not quite same physical size (12.5 v 10 & 8mm dia), but I reckon there's room if I leave the tails long on some (and insulate) - just hope tails aren't too thick for the holes in the board.

On closer inspection, one larger cap is at 30 degrees and has splattered the board, one smaller one has cracked the X on the back and crusted - how can electronics work at all with such knackered components????

The caps are part of a smoothing circuit. Just means that the power going to the board isn't properly smoothed aznd so you will get spikes which can cause crashes and premature component death.

biomulv' date=' re. Farnell Electronics, just too late, but thanks anyway, looks very useful and no doubt I'll use in the future.

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Back in the day id always use farnell for components over RS, RS was usually just for the more industrial stuff then. They have always beaten RS when it comes to obscure components for me.

Hope yer MB lives for a while longer.

If not I have a K7 AMD board that i have repaired and is running that you can have for the postage costs if you want.

Cheers biomulv generous offer, I'll see how it goes with my soldering.

no worries. get a small tip for the iron and turn the temp down a bit if you can.

let me know how you get on on

Well I actually got a new PC, but yesterday I finally got around to taking the old one to bits.

As it was apart I had a look inside the power supply unit and something (once rubber coated) was obviously overheating so I got a 20 quid replacement first - made no difference.

Today I soldered in the replacement capacitors and I'm posting with it now! It flies - every thing seems speeded up and smoother (mouse response, video etc.) is that possible?

Anyway pending a few hours soaking to expose my rubbish dry soldering I think I can call it a success.

A big thanks to Biomulv and Cheezemonkhai for the advice and encouragement as I can still get a lot of use out of it as a spare and I learnt a lot about the inside of a PC too!

Now worries , glad to hear you got stuck in, and all is well. Where did you get the caps in the end ?

Yeah if the CPU voltages are swaying then the clock will possibly be affected.

Glad it's sorted

You will find those dodgy caps in so many things. What i would say is be damn careful what yo ustart taking apart, i tend to not take PSU's apart except for fan replacement. The PSU for example has some very large caps etc in it that could potentially kill you if you touch the wrong part.

Also farnel are good i just said RS as that is who we used when i was repairing and also where we use as one of our suppliers at work.

Still working :eek: , and no strange smells anymore.

I got exact matches from RS, replaced two little ones and three big. That cleared the board of all that make (RLE black/gold). One of the large ones had blown/burnt the end off completely.

Re: the PSU, as it was so cheap to replace and readily available I didn't think it was worth messing around with that. Fortunately I know capacitors can hold a kick - but a worthwhile warning.

Cheers guys.

Burnt end off :o:o, hope it was just cruft instead but that could have been really nasty :S

Still amazing what 20 mins plus a couple of £ of caps can do hey

In case anyone is interested, has same problem etc. - piccies:

Old cap top and bottom (ready to pop, this was not the worst one, the bigger ones had got so hot that the gold stripe was almost black). The silver X tops should be flat! The plastic/rubber bottom is almost carbonised and flaking off.

Repaired board, one of the larger caps is installed 'flying' as the replacements were too wide to sit side by side. The board actually had 'twin' holes to allow easy fitment of caps with wider-spaced terminal wires.

Many boards were twin holed for Caps as this means the manufacturer could use whichever caps were cheaper that week

You are going abit retro there with a slot CPU, but then i'm still running a PIII 550 rig