How to tell if Motherboard is Faulty?

I am having troubles with my new build. I put all the components together but when i turn the computer on i get a flashing red DRAM light and no screen display. Also the usb inputs (mouse and keyboard) are not registering so i can not enter bios. I am suspicious that it is either my cpu or motherboard causing the problems as those are the two parts that are not new. Here is my build:

Mobo: Asus P8B75-M
PSU: Corsair CX500
Case (may not be relevant): Coolermaster silencio 550
CPU: Intel i3-2120 lga1155
SSD: Samsung 840 series 250gb
ROM: LG Blue Super Multi
CPU Fan: Coolermaster Hyper 212 Evo

Edit: Another bit of info, all fans seem to work when turned on.
18 answers Last reply Best Answer
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  1. RAMs might be relevant - what model?
    Have you tried starting the board with single RAM installed?
    If still the same, test the board outside the case.
  2. Yes i have researched the topic and most people believe it to be the ram however i took the ram from my first build which works fine and put it into my new one to ensure it wasnt that and still had the same problem. Ram is G skill - Ares. Yes i have tried with single ram in all slots one at a time.

    By the way this is my first time posting so thanks heaps for the fast reply.
  3. Fo ruling out a short, try starting the board outside the case (put it on its cardbox). Is the CPU fan spinning when starting the computer?
  4. Yes the Cpu fan is spinning, as is the case fans.
  5. Try taking it though outside the case and make sure that the RAM module is properly inserted. Try also clearing the CMOS (unplug the power cord and remove the CMOS battery for few minutes).
  6. I have tried the CMOS solution, didnt work though. I will try taking it out of the case, but just curious why does taking it out change anything?

    Edit: Also, just wondering is it normal for system to continuously restart loop while holding the MemOk! button?
  7. Best answer
    An extra standoff would short the board and could create this kind of issues. This way you would know it isn't about a short.
    If still the same outside the case, then yes, it might be a faulty board (assuming that the RAMs are compatible).
    No, the restart loop is not normal.
    I would also try reseating the CPU and inspecting the CPU socket for bent pins.
  8. I tried what you said, no luck. Just wondering is it possible for a broken cpu to damage a motherboard?
  9. Broken CPUs are very rare. It's either a memory issue or a board's one. I suggest testing the components at a local shop or RMA-ing them (I would RMA the board and the RAMs).
  10. Okay so i figured out its not the cpu. I decided to have a look at the cpu socket after taking it out and I'm pretty sure i found my problem. Bent pins in the cpu socket.. :/ is there any way to go about fixing this or is it too dangerous?

    Edit: Just realized you said to do this earlier 'I would also try reseating the CPU and inspecting the CPU socket for bent pins.' - alexoiu
  11. "flashing red DRAM light " what else is it supposed to be for if not the ram?

    What is the make model speed volume of your ram? It's most likely the culprit.

    Edit - bent pins? as long as they are only leaning you can lean them straight again but if they are like a dog's hind leg then they are most likely wrecked, it's virtually impossible to straighten an iron bar once it's been bent.
  12. Can you post a picture of the socket?
  13. Sorry but how do i post pictures? Oh and TenPc I know it would seem as though it is the ram however i have tried testing the ram on another motherboard and they worked fine (so its almost definetly not).. Also what exactly do you mean by a dogs hind leg :P

    Edit: Is it just copy & paste for pics?
  14. Just to update it was definitely the cpu socket on the mobo, there were several bent pins and one broken one. I took the broken pin out and straightened the bent one. Turned on computer (i know it was dangerous) and bam it works fine now. Thanks heaps for all your help alexoiu and to you too TenPc.
  15. Dogs don't have straight back legs, they are always a bent at an angle.
    One broken pin, it is most unusual for the CPU to actual work, you might find issues later on when demand is high for CPU usage.
    You should try to acquire a replacement (CPU) asap so those issues don't come up.
  16. Umm yeah but its an lga 1155 socket on the motherboard not a broken cpu pin.. (sorry i dont understand what you mean.. why would i buy a new cpu when its not causing the problem?) :)
  17. "there were several bent pins and one broken one. I took the broken pin out and straightened the bent one"

    What are those pins for? To hold up the CPU?
  18. Yup, you know what an intel motherboard looks like right? The cpu socket has the pins which come into contact with the underside of the cpu itself.. :)
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