PC woes

[Dave Plowman (News)]

It has 2GB in four sticks.

[Dave Plowman (News)]

Right - determined to sort this out today.

Started the machine (for the first time today) in setup and found the page which gives CPU temperature, etc. Said should be 72C. Over the short period I watched it it climbed from 50C to 80C then shut down. The fan was running normally.

Is there anything that could cause the CPU to overheat this quickly - some form of abnormal load?

[The Natural Philosopher]

Bad heatsinking. Bad CPU.

[AJH]

In the BIOS?

I think you must mean that this is the CPU shut down temperature, which explains what was happening.

It points to a poor joint between the heat sink and CPU, your wiggling it may have made it worse. After you clean both surfaces (propyl alcohol maybe) use some heat sink paste to get a good connection.

I forgot what CPU you have but IIRC a p4 2GHz dissipates 67W, so it cooks in seconds.

AJH

[dennis]

The heat sink is not fitted correctly.. take it off and do it again. Next time buy an Intel.

[Dave Plowman (News)]

Think so. I'm not really a PC person. ;-)

No - it said something like target temp. Can't look at it now as it's in bits.

It seems to have been making pretty good contact - although it's possible I was over generous with the paste. I've removed it all including CPU and cleaned it all up. Will re-assemble after this coffee. ;-)

Right. It's an Athlon 64 3000+

One other thing I found - not being well up on cable select, or even reading the instructions on the HD - I'd set it to master but had plugged in into the slave connector of the cable. So the BIOS reported no master but slave only. I'd also set the two CD writers to master and slave on the other IDE bus.

[Dave Plowman (News)]

Whatever I've done has made it worse. It shuts down just after showing the BIOS page at startup.

[Mark]

Normally with paste you only need a tiny amount. Apply some on the heatsink and spread it out over the contact area. Now scrape off the excess. A common mistake is to have too much.

See

I don't put any compound on the CPU itself, only on the heatsink.

These produce a lot less heat than a P4 IIRC.

If you have set the jumper to master then it is irrelevant which connector you use.

[Andrew Gabriel]

Sounds like no contact with heatsink at all.

(If you did that with the really early AMD hammer, you heard a crack about 2 seconds after switching on, which was the CPU case cracking in half;-)

Can you get the ZIF leaver up with the heatsink in place? If so, do that and lift the heatsink off. It should come off with the chip, as a thin layer of heatsink compound correctly applied actually takes a bit of pulling apart, like a rubber sucker.

[Dave Plowman (News)]

The BIOS reported it as master not present, but slave only. I was hoping correcting this might speed up the damn thing.;-) But it's totally fooked at the moment anyway. I'll look at it again this evening.

[Dave Plowman (News)]

It was indeed truly stuck. It looked to have been making very good contact indeed. I'm wondering now if I got some of the paste in the CPU connector. Is it possible to strip it down to clean it properly?

[Andrew Gabriel]

I really doubt it. I think you would have to be unlucky for it to prevent the socket working, unless you got loads in there. I imagine any attempt to dissassemble one of those sockets is highly unlikely to work afterwards.

Check carefully for bent/broken pins on the chip.

I might try reseating anything else pluggable, incluing leads (power connector particularly).

[geoff]

In message , Andrew Gabriel writes

Just a thought ...

is the heatsink on back to front ?

[Dave Plowman (News)]

To the best of my knowledge it's not handed. Looks to be symmetrical.

[geoff]

In message , "Dave Plowman (News)" writes

The voice of experience says

"CHECK"

I managed to get it wrong once

one way round the heatsink sits nicely on the CPU, the other way round ... it overheats because it doesn't

[Dave Plowman (News)]

Well, it's been on the same way round since I built the machine and worked ok for a year or so. I know this because of the cable to the fan.

But I'm not convinced it's a cooling problem. I'm thinking a broken track or dry joint round about the CPU.

But just for you I'll turn it round...

No difference.

[Rod]

Assuming still not sorted, have you cleaned the heatsink?

Some designs accumulate much better than a Dyson/Henry/Miele/. A surprisingly small amount of dust/dirt in the wrong place can reduce effective cooling in that area. You did clean it thoroughly when you took it out, didn't you?

(I saw you had clreaned off the thermal paste - maybe you meant to say that you had cleaned the whole thing? Apologies if you have already completed your housekeeping badge.)

[Dave Plowman (News)]

As I said it appears symmetrical. Nor are there any markings on it. And it can only be fitted one of two ways due to the clip. Do you actually know the type of heatsink supplied with the Athlon 64 3000+ ? And how would you account for it working ok for over a year if fitted incorrectly?

Looking that way.

[dennis]

You were lucky if you did that! Putting the heatsink the wrong way on older AMD CPUs would have destroyed the chip! The word was check not just try it.

You can get a new cpu and MB for about £99 which is probably the easiest solution.

[Dave Plowman (News)]

No. It looked quite ok.

No again.

I will do just that now.