GA-P55A-UD3 + i7-860 = no boot

[ogge99]

Hello,

I have the following specs:
PSU: Fractal Design Integra 500W
Motherboard: Gigabyte P55A-UD3 (BIOS version F11)
CPU: i5-650, 3.2 GHz
CPU cooling: Cooler Master Hyper 212 EVO
RAM: 2x2 GB 1333MHz DDR3 ("G-HS")
Graphics: GTX 670
Storage: 1TB Samsung HDD SATA2

A month ago I bought a used processor online, for a minor upgrade, an i7-860. From what I can see the motherboard is compatible with this processor, as long as the BIOS is version > F5 (mine is F11). Considering what I've read on different forums the 500W PSU should be enough to at least power up the computer...

Problem:
After installing the i7-860, the computer wouldn't boot, no post, no BIOS etc. It's only a half-second kind of boot, phase LED showing green/green/orange/red, fans (CPU, GPU, chassi) spinning also for half a second, no beep etc, not alot to work with. After shutting down again, it starts to boot after a couple of seconds, it boots for half a second with the behavior described above, and then there is a never ending loop of failed boot attempts.

I did the following:

-Reset CMOS (both removing battery and clear_cmos pins)
-Tried without GPU, HDD, unplugged everything except CPU+ram, no change
-Tried with older GPU, HD5770, no success
-Reseated CPU, double-checked the amount of thermal paste
-Checked bent pins, none are bent
-Checked that 24 pin and 8 pin are connected to motherboard
-Changed slot position on both RAM sticks, tried one individually in all slots
-Changed wall socket + psu cable
-Follow this guide carefully: http://www.tomshardware.co.uk/forum/261145-31-perform-steps-posting-post-boot-video-problems?_ga=1.247157764.1053945368.1476737032 (double-checked everything, noteworthy: boots with old cpu, see below)

When I insert the old CPU, everything is fine again, and the computer boots without any problems.
This led me to believe that it was either me screwing up by not clearing CMOS/setting fail-safe defaults on BIOS after removing the i5-650 and before installing the i7-860 (I had overclocked the i5-650 before), or that I had been sent a faulty CPU.

Today I received another i7-860 from another seller, installed it carefully, and I get the exact same no boot behavior... Half a second, nothing on screen, doesn't reach BIOS or anything obviously, no beeps. This time I reset the CMOS before installing the CPU, was wearing anti-static wrist wrap and was very careful when I installed the CPU.

I find it unlikely that both these CPU:s are non working. I expect the PSU not being able to boot with the i7-860 since the i5-650 requires less power, however, 500W seems to be fine for this kind of setup.
Just to clarify, when I install the i5-650, everything is fine, computer boots and is fully working.
Could it be the RAM not being compatible with the CPU? Or the PSU in some way not being compatible with the CPU?
At the moment, I unfortunately don't have any other PSU or RAM lying around, and I don't have the money the buy new RAM or a PSU just to see if it works. I understand that trying with another PSU would be wise, but I can't get a hold of one in a month or two...

Any ideas?

Thanks a lot in advance

TL;DR: Computer does not boot with 2 different i7-860 processors even if it should be compatible.

 

[alexoiu]

Hi. I'd say that the processors are defective, but... it's just a guess.

 

[ogge99]

Hi. I'd say that the processors are defective, but... it's just a guess.

@alexoiu Thanks for replying. How unlikely do you think it is that the PSU is the problem? (the PSU is working fine with the old processor). I understand that it is hard for you to guess. I did however remember something. When I first received this computer it was showing the exact same split second-boot-behavior when the 8 pin (or if it is 6, can't remember) CPU cable wasn't connected. If 500W for some reason isn't enough, or if there is something else wrong with the PSU, could it be possible for it to still work with the older processor, but fail with the i7 (which requires more watts)?

 

[alexoiu]

You're welcome. Not sure about the answer here. It would be good to test the processors with different board / at a local pc shop, if possible.

 

[ogge99]

You're welcome. Not sure about the answer here. It would be good to test the processors with different board / at a local pc shop, if possible.

I have now tried with a another (working), more powerful (630w) PSU to rule that out. Still the exact same behavior. Have you heard of any motherboards that for some reason boot with some CPUs but not others (both being compatible)? Or do you think is it safe to say that the motherboard is fine since it is working with the i5-650?
In that case I have narrowed it down to the CPU being faulty. I find it kind of unlikely that two different sellers, none of who I payed before trying, both would have sent faulty CPUs, but I guess that is the case. The only other thing would be the Cooler Master Hyper 212 EVO for some reason being mounted incorrectly on the CPU. It has however been correctly mounted on the i-650 every time I installed it, and has shown good temperatures...

Thanks

 

[ogge99]

An update/change in behavior:
With the new (borrowed, it's actually kind of old, new for me though) 630w power supply, after unplugging the 2x4 pin cpu power connector from the motherboard, the boot attempt is a bit longer, from half a second-ish to about 1.5 seconds. That feels kind of weird. Any ideas on what it could mean?

Edit: After looking at the socket with a magnifying glass and inspecting every single pin, one appears to be slightly slightly "bent" or out of place. Would that explain why one CPU could work and another? If for example i5-650 cpu:s use the pins differently than i7-860?

 

[ogge99]

Thanks for all replies/advice/help.

So, I finally got it to boot somehow. Couldn't believe my eyes.

What I did, if anybody finds this thread (not sure which one fixed the issue though):

-Changed PSU from a 500W to a 630W (don't think this hade any impact), both PSUs crappy brands
-Cleaned out some dust from the corners of the motherboard socket with compressed air
-Re-angled (rip english) a motherboard socket pin which was slightly angled in a weird way, not at all bent, but didn't align 100% with the rest (note: the i5-650 was working fine with this "defect", which I hadn't previously seen before going through everything carefully with a magnifying glass before giving up on the project)
-Blew compressed air over the entire motherboard basically
-Cleaned the i7 with alcohol electronics cleaning spray stuff until it was nice and shiny
-Changed CPU cooling from a Cooler Master Hyper 212 EVO to an Arctic Cooling Freezer 7 PRO rev2. Got this idea since the booting behavior was exactly the same when there was no CPU installed. Perhaps I installed the 212 EVO wrong every time I tried both of the i7's, not likely though since I installed the cooler fine with the i5 every time

...and voila! It booted. Works like a charm now!