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I just built a new computer and I'm having an issue and want to know if this is CPU or Motherboard.

The hardware is:

  • ASUS P8Z77-V PRO
  • Intel i7 3770k
  • Cooler Master Hyper 212 EVO Heat Sink
  • Antec 750 Watt Power Supply
  • G.SKILL 16GB memory

Ok, so I hook everything up outside the chassis. Here is everything I hook up: Put CPU in, Cool Master heat sink, memory(which I don't think is needed to test) and power supply.

I've connected the

  • 24-pin power connector
  • 8-pin CPU power connector
  • Power button connector
  • Couldn't find a speaker on the motherboard or in the chassis.

So the motherboard is getting power, the heat sink fan comes on and other lights on the motherboard come on. However, I'm not getting any signal to my LCD display and I notice the heat sink fan starts up high but quickly slow down a notch(which might be normal).

Would this be a motherboard or processor issue? Also, do you have to remove thermal paste from CPU before returning it?


share|improve this question
do any of the 3 red lights on the motherboard light up? There's a CPU, a memory and one more light. CPU lighting up may mean CPU or motherboard damage - With mine, a pin on the motherboard kept it from booting, and that lit up the CPU light – Journeyman Geek Dec 26 '12 at 2:41
I have had a similar issue on a build and it turned out to be the power supply. It was a brand new AZT 900 watt. That might be a place to check as well. Even though fans sping up, it was still the PSU. – Carl B Dec 26 '12 at 2:54
I can't remember what lights are coming on. I'll put everything back together. Just wondering, I removed the heat sink so do I have to clean the remove the thermal paste from the CPU and heatsink and reapply thermal paste? Or can I just use what was on it from earlier today? – Michael Dec 26 '12 at 3:04
You SHOULD reapply a new layer of thermal paste every time you remove the heat sink from the processor. Telling you anything else would be irresponsible. Have people gotten away with not doing that? I'm sure they have, but it can't be advocated. Of course, most people don't realize just how little thermal paste you are supposed to use... but that's another story. As has been pointed out, your issue might not be either component you are worried about. – Bon Gart Dec 26 '12 at 3:30
Ok, I tested everything again. As far as lights, two come on which are standby power LED and DRAM_LED. The DRAM_LED near the MemOK! switch lights continuously which according to the manual means the DIMS are incompatible with the motherboard. Also, when putting the CPU into the socket it appears one of the motherboard pins are bent but the POST state LED of the CPU doesn't doesn't come on so maybe it's ok. I also tried holding down MemOK! but that didn't help. – Michael Dec 26 '12 at 5:06

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