• Happy holidays, folks! Thanks to each and every one of you for being part of the Tom's Hardware community!

Question Major issues with... everything. CPU Light on!

Feb 27, 2019
2
0
10
Hey guys, I’m super new to this whole forum, so sorry if my title is confusing. I’m having major issues with my whole PC.

Just 2 days ago I went to bed and left my PC running as I usually do. I woke up in the morning to a laggy mess and couldn’t figure out what was wrong until I got a warning that my CPU was cooking at about 90 celsius. I immediately shut down my PC and quickly figured out the pump on my Fractal S36 had died. No big deal, it happens (although it wasn’t covered by warranty because I bought it used).

Yesterday I went out and bought a Corsair H100i Pro and swapped it out with my old S36. I made sure my power was off when installing and while I was at it, checked to make sure all of my cables were properly installed. I went to boot my PC and was immediately met with my CPU light on. Unsure what was going on, I looked it up and decided my best route of action was to make sure my new cooler was seated properly and my thermal paste was a-ok.

I did that and upon my next attempt to boot was met with a DRAM light. Again, I looked up what to do and tested each RAM slot with a stick of RAM I knew was good that I borrowed from my roommate. Still, the DRAM light was coming on. Finally, I reset my CMOS by shorting the pins with a screwdriver.

This leads to where I am now. I’ve breadboarded the whole PC to make working easier. When I tried to boot, my DRAM light turned on then flicked to my CPU light. The two will turn on alternately for 20 seconds before my PSU will make a small clicking noise (the same sounds it makes and has always made when turning on/off) before shutting down the whole system. Complete failure to POST.

I’m at a loss of what to do. If yalls could help, it would be greatly appreciated.

Specs
CPU: I7-7700k
Motherboard: Gigabyte Designare Z270
CPU cooler: Corsair H100i Pro
RAM: Tridentz RGB DDR4-3000 (2x8gb sticks)
PSU: Corsair RM 850i

Unrelated specs
Case: Phanteks Enthoo Evolv
GPU (uninstalled because it isn’t part of the problem): EVGA GTX 1080 ti
 
I would also suspect the CPU. I've had an i7-7700K fail on me. It was the last component that I replaced when diagnosing the problem after having replaced both the motherboard and memory.

I RMA'ed the faulty CPU to Intel and got back a replacement that fixed the problem.
 
Last edited:
I would also suspect the CPU. I've had an i7-7700K fail on me. It was the last component that I replaced when diagnosing the problem after having replaced both the motherboard and memory.

I RMA'ed the faulty CPU to Intel and got back a replacement that fixed the problem.
Just did the paperclip test, PSU is blown. At this rate, I'm suspect that the whole PC might be toast