[SOLVED] cpu has strange white spots on bottom

Solution
With the current design of Intel processors, as well as computer systems in general, it is not possible to eliminate the incidence of contact fretting in the area you have pictured.

You CAN slow the speed of fretting by increasing the clamping pressure of the processor to the processor socket, reducing the temperature of the contact surface to 60°C, reducing the humidity of the environment, reducing the vibration within the computer case (implying a move to SSDs, eliminating fans, and moving pumps and radiators outside the case), and running the processor (and memory) at lower voltages.

An argument can be made for the application of non-conductive silicone grease to the processor socket, to lubricate the contact surfaces, but...
With the current design of Intel processors, as well as computer systems in general, it is not possible to eliminate the incidence of contact fretting in the area you have pictured.

You CAN slow the speed of fretting by increasing the clamping pressure of the processor to the processor socket, reducing the temperature of the contact surface to 60°C, reducing the humidity of the environment, reducing the vibration within the computer case (implying a move to SSDs, eliminating fans, and moving pumps and radiators outside the case), and running the processor (and memory) at lower voltages.

An argument can be made for the application of non-conductive silicone grease to the processor socket, to lubricate the contact surfaces, but the question remains as to whether the socket materials are compatible with silicone grease. Doing so may just make the situation worse, so I wouldn't recommend it for any system that you are not willing to sacrifice to an experiment.

Processors having pins that mate into a ZIF socket are less prone to the failure mode, but are not immune to it; so, moving to a processor that uses pins will reduce the problem somewhat.

All-in-all, being aware of contact fretting, and structuring your maintenance cycle in a way that accounts for it, is probably your best move; and, it looks like you were on your way to observing some weird issues with the system, had you not decided to do some upgrade work now.
 
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Solution
Let me add this:

Anytime you run into issues of crashes, memory or hard drive errors, or video 'weirdness', out of the blue, your very first action should be to open up the system and disconnect EVERY connection point and un-make and re-make the connections several times, then seat all connectors fully.

If the issue is contact fretting, just doing this will clear up the problems--for about as long an interval as before the problem first cropped-up. Better that you do this for yourself, than paying somebody else to do it for you.
 
Sep 10, 2016
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With the current design of Intel processors, as well as computer systems in general, it is not possible to eliminate the incidence of contact fretting in the area you have pictured.

You CAN slow the speed of fretting by increasing the clamping pressure of the processor to the processor socket, reducing the temperature of the contact surface to 60°C, reducing the humidity of the environment, reducing the vibration within the computer case (implying a move to SSDs, eliminating fans, and moving pumps and radiators outside the case), and running the processor (and memory) at lower voltages.

An argument can be made for the application of non-conductive silicone grease to the processor socket, to lubricate the contact surfaces, but the question remains as to whether the socket materials are compatible with silicone grease. Doing so may just make the situation worse, so I wouldn't recommend it for any system that you are not willing to sacrifice to an experiment.

Processors having pins that mate into a ZIF socket are less prone to the failure mode, but are not immune to it; so, moving to a processor that uses pins will reduce the problem somewhat.

All-in-all, being aware of contact fretting, and structuring your maintenance cycle in a way that accounts for it, is probably your best move; and, it looks like you were on your way to observing some weird issues with the system, had you not decided to do some upgrade work now.
Thank you, so basically it’s wear and tear of the system. Anything I could do to improve the fretting on the CPU or no? I was planning on selling it but not sure if that’s going to happen now.
 
::: sigh :::

Well, if it was MY system, I'd be using pure silicon grease on the contacts (and a VERY thin film of that at most) and cranking the processor engagement down as far as I could, without damaging things.

At best, it would be one of those grand experiments that I'm prone to do when I don't care if I tank things or not, and count it as a win if the system survives. Unfortunately, I have several shelves in the garage dedicated to the storage of the carcasses of systems that didn't quite make it.

I would highly recommend that, if you care about having the system operational for any reason, don't follow my example.

You could try polishing the socket contacts with a pencil eraser, and blowing out the eraser bits with canned air; but I am circumspect about trying that on a processor, because of probable static damage.

For the processor, the most I would probably try is to lay a new dollar bill flat on a hard table surface, and set the processor down on it and press it down with medium force, and push it from one end of the bill to the other--only once--then try it in the system. Dollar bill notes are actually abrasive enough to do a good job at removing the cruft from the processor.

Now that I've said what I might do.....I'm telling you now:

DON'T DO IT. You might be disappointed in the results.

Then again, if you do it and it works, you can sell the system with a free conscience.