CPU or Motherboard Problem ? - OS Bootloop

[sivrintear]

Hi

I have a 2500k on a Gigabyte GA-Z77X-UD3H Rev1.0 motherboard running the latest bios.

I have two oddities that I have experienced and then a event yesterday.

1) If I change my ratio above 33 the clock speed doesnt change (I havnt overclocked in a while but this did work).

2) Yesterday I had a error that involved me having to re-install windows 8 (The one where it wont boot then in setup says hard drive locked) however I unplugged my 560ti and xonar d2x and ran off the onboard, I would get as far as logging in and then my pc would reboot, it would do the same during a ubuntu live distro I tried, it would mostly happen when it comes to loading the desktop environment but never if I left it in bios or running a memtest (tested all 4 of my memory modules, no errors). I finally decided to try with graphics card back in and it works fine.

I would like to know if this would be a CPU or a motherboard issue as its easy to get the motherboard RMA'd but not the CPU.

I know there are threads on this problem but I havnt seen an exact point of error more the fix of using a graphics card.

Thanks in advance.

 

[ryan27968]

99.999 percent of the time, if you are wondering if the cpu or the motherboard has failed, its the motherboard that is faulty. cpus are pretty darn durable and do not fail easily(unless it overheated but in most cases this wont happen)