Is my CPU damaged? Pics included

[Blodo]

Hey guys. First post here.

I just want some pairs of eyes to look at my problem before I go ahead and replace my CPU. Basically a few days ago I was restarting my PC after a windows update, and heard a loud spark with a flash instead and then the PC shut down. Turns out the PSU cable was loose. I tried to turn it on afterwards, only to be met with a complete freeze, no POST, no beeps, no nothing - but crucially, the fans were still operating and the computer was "on". I turned it off and on a hunch, turned it on again and this time it booted, POST successful, managed to get all the way into Windows and then froze. Cue another hard reset, this time it booted and worked for longer but the freeze problem persisted. Also, it would usually take a few tries before I managed to get it to POST and boot from a cold start.

I replaced the PSU thinking that that was the issue (and to calm my paranoia about possible voltage spikes), but the problems persisted. This made me think that it must be the motherboard, so I took the PC apart, took out the heat sink and saw this:

On the picture you can see discoloured areas on the base of the CPU, I think this may have happened because of the spark. The area around the CPU dock on the motherboard was also heavily discoloured, almost as if slightly burned. I built this PC specifically with temperature flow in mind, under load none of the temps ever exceeded 45C so I'm skeptical that this might be from general use. The CPU technically sorta works, but the increasing instability is a big problem for me. Before this incident the PC was perfectly stable.

The specs related to this issue are:
PSU: Corsair TX 650W '80 Plus Bronze'
CPU: Intel Core i5-3550 Ivybridge
Heatsink: Arctic Cooling Freezer Xtreme Rev.2
MOBO: ASRock Z77 Extreme4 M Intel Z77

I already ordered a motherboard replacement since it seems logically that that is the next possible problem component. Should I also order a new CPU or can this be just the motherboard causing it?

 

[harendra410]

http://www.tomshardware.com/forum/357010-28-pins-discolored

check this out

 

[Blodo]

http://www.tomshardware.com/forum/357010-28-pins-discolored

check this out

Looked, but that's not the problem I have. The discolouration on the motherboard isn't on the pins (funnily enough they look fine), it's around the metal bit holding the processor down on the pins like so:

 

[harendra410]

it looks like overheating the cpu and i think there must be a serious damage to the proc i recommend you to take it to a professional and check whether it is working, if it is not you will also have to order a new processor.Please check your cooling system(CPU fan) before installing it to the new MB because there can be a problem exits with that

 

[Blodo]

It's not the cooling like I wrote in my first post. When I built this PC 2 years ago I paid special attention to stress testing and good airflow. Temps never rose above 45C during load. The CPU fan definitely works, its one of the first things I checked and I also paid special attention to temps right after the freeze by booting into BIOS and checking them there. It's the result of the power spike I'm sure of it. Technically it still works, but it tends to freeze often and has intermittent trouble with POSTing.

I guess I should just install the processor in the new motherboard and stress test it before ordering a new one?

Edit: I stress tested the CPU on the old motherboard before disassembling it, out of three attempts, one was an almost instant freeze, the second froze after about 30 iterations in prime95, and the last one ran without any trouble over at least 50 iterations. Temps were as expected during that time as I had coretemp running in another window to make sure things aren't overheating. The instability seems kinda random.