Fixing bent pins on a CPU

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While replacing a mainboard in a desktop machine (see related question), I did something stupid. I inserted the CPU into the new mainboard, but didn't check for the right position. When it didn't immediately lock in, I pressed slightly before realizing what was wrong. The result was a number of bent pins.

I tried every tutorial that popped up when Googling "CPU bent pins" - using credit cards, sewing needles, and a hunting knife to get the pins back into position - but to no avail: For every pin I get straightened out, two others are bent.

I have no problem getting individual pins straightened out, but my many attempts have led to many pins being slightly askew - enough for the CPU not to fit into the socket (An AMD X3 one). Maybe I just lack the motoric finesse. What I would need is some sort of a grid to fix all pins at once.

It's a €50 processor so the loss is not catastrophic. But I thought before I go buy a new one, I thought I'd check here whether anybody knows some magic trick, or a cheap generally-available tool to fix this.

Update: it turned out that the CPU was beyond salvaging: A pin broke off in the end, which made me give up. I bought a new CPU. Still, thanks a lot for the great input, and I think this is a useful reference for future generations.


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Pekka

Posted 2011-01-05T12:00:28.047

Reputation: 2 239

3The Credit card should not cause any pins to get bent.. From what I remember from what I figured out from how I used it, the idea with the credit card is you slide it in and ensure a line of pins all go straight so any bent one gets fixed with the rest. If you are bending other pins while fixing one then you're using the credit card wrongly! – barlop – 2011-01-05T18:32:51.393

2

Broken pin != broken processor. There was story on http://ithappens.ru where something other was used as pin (without soldering), also there is chance that it will work without some pins (especially if it is ground pin)

– Vi. – 2011-04-16T16:51:53.107

1Be very careful not to bend the pins too many times, in my experience they turn brittle very quickly and snap. Good luck – Jay_Booney – 2011-01-05T12:11:29.507

Answers

26

Mechanical pencil is what I've always found to be best for this job. If you leave out any graphite and use the hole at the end you would normally write from it should fit snugly round the CPU pins.

evesirim

Posted 2011-01-05T12:00:28.047

Reputation: 448

That's exactly my tool of choice - either that or a thinner-than-normal plastic 'biro' insert (eg: from a small pen that comes with a pocket diary) - cleaned out with a paper clip and washing up liquid. – Linker3000 – 2011-01-05T14:19:36.123

Cheers. See the updated question for the conclusion. – Pekka – 2011-01-12T16:28:07.030

5

Tweezers should do it. Have you tried them?

I think I used them once. I read about it along with the credit card method! You may want to use both But from the sound of things, tweezers would be more useful to you.

barlop

Posted 2011-01-05T12:00:28.047

Reputation: 18 677

1Interesting - no, I haven't tried that, I tried with objects with only one handle. I may go to the drugstore and buy a pair later, why didn't I think of that? – Pekka – 2011-01-05T12:05:41.240

@Pekka I just read of it back when people read computer magazines! It's not as common as a screwdriver or another big hefty manly tool like a sledgehammer which you may not have used but you'd think of. – barlop – 2011-01-05T12:07:26.890

3

My suggestions

  1. Hold the CPU tight
  2. bend the pin at the bottom of the pin to make it straight at bottom, then use a tweezer to hold it at that particular place. (The rationale here is that the worst thing you can have is breakage of the pin at the bottom of the pin nearest to the CPU, which is exactly the place of highest stress if you use tweezers to hold it.
  3. while holding the base of the pin adjust the top of the pin (faraway from the CPU). try not to make too many tries.

bubu

Posted 2011-01-05T12:00:28.047

Reputation: 9 283

0

All the handling involved with your trying to fix the pins has likely degraded the cpu due to ESD.

For future (in case it happens again and it's an expensive cpu): As one person recommends here, you can get a mat and wrist strap for handling integrated circuits like this (ESD protection). As for the pins, a good electronics store should sell pin pusher type tools that will slip around the pin and allow you to precisely align individual pins.

Additional Bonus -- For those unbelievers: Notice I said "likely degraded," not catastrophically dead: Here is what Mike Meyers had to say about the matter in his A+ Certification Passport (2007):

ESD is one of the main enemies of your computer. To maintain your computer and prolong the life of components, you need to learn about the effects of ESD and how to protect your computer from those effects[...] even discharge well below the level that you can feel can damage or destroy PC components.

ESD Degradation: ESD degradation occurs when the effects of ESD are cumulative. This is caused by situations where low levels of ESD occur repeatedly. Damage caused by ESD degradation is not immediately apparent in full force[...] degradation will cause your components to behave erratically.

One of the most important steps you can take to prevent the effects of ESD is grounding yourself before you handle PC components."

Then Mike goes on to talk about wrist straps, which I mentioned above.

Flotsam N. Jetsam

Posted 2011-01-05T12:00:28.047

Reputation: 1 291

That is well possible. Still, I will try and invest a half hour of further trying before I buy a new one. – Pekka – 2011-01-05T16:01:15.057

That's unlikely. – Sathyajith Bhat – 2011-01-05T18:00:17.997

@Sathya: Really? See my edit. Is Mike full of it? – Flotsam N. Jetsam – 2011-01-05T18:26:46.937

3-1 for obvious troll bait. The ESD debate has nothing to do with this. The question is about how to straiten pins. While it is possible that the CPU is dead due to handling, you'll never know until you plug it in. If the person has the time to waste on this, they might as well give it a shot. – Doltknuckle – 2011-01-05T18:45:18.237

Of course it is possible the CPU to be already damaged but it is also possible it is not yet and not trying to repair it would be at least a waste! In fact I already had this problem a few years ago on several Athlon CPUs, I used the mechanical pencil way and they are still working. – laurent – 2011-01-05T18:53:44.463

1OK. I removed my suggestion for not even wasting the time. – Flotsam N. Jetsam – 2011-01-05T19:02:32.007