I have an i7 2600k CPU and it was purchased brand new and the motherboard that I first tried installing it on was a MSI P67A-GD55 (B3) and I had all the DIMM slots full with DDR3 1600 memory. When I started the system for the first time all it did was come on and go off a second or so later then it came back on again. It did that continually so I started pulling memory sticks out so that it only had a single stick. It came up to the post screen right away. I added a second stick so it would run in dual channel mode, turned on the computer and it started right up. Then I added a third stick and tried it that way and as expected it wasn't runing in dual channel mode any longer. I then installed the final stick and turned it on, it went right back to the on, off looping issue. I pulled every stick except for the last one I put in. I turned the system back on and it went to looping, I tried every stick of RAM in that DIMM slot and all of them went right to the looping deal again. I figured that it was just a bad DIMM slot so I RMA'd the board. The company wouldn't accept it when it got to them say that several pins in the cpu socket were bent and twisted beyond repair so they sent it back to me. I looked at and couldn't see anything wrong with it. So I figured I was just going to at the cost of that board. I ordered another board this time a MSI Z68A-GD80 and was extremly careful installing the CPU on the board. I installed all of the memory and it fired right up to the post screen and it was running at the default settings so I made a few changes in the BIOS and it continued to work just fine so I went ahead and installed Windows 7 Ultimate 64 bit version. That went off without a hitch. I shut it down for the night as it was pretty late to do anything more with it.
Well the next day when I turned it back on it went right back to the on/off looping deal. I pulled the memory and with one stick it loaded right up. I kept adding each stick and all was fine until I got to what was basically the same DIMM slot that I had problems on the other MSI board. As long as I leave that one DIMM slot empty it will run so I pulled the third stick so it would run in dual channel mode. I had posted this on MSI's forums and most who tried to help were stumped since the very same thing happened on two different MSI boards. I did try every stick of RAM and they all worked except for the second DIMM slot. One suggestion was that maybe my i7 2600k had a bad memory controller so now I'm looking for some help with this problem. I did update the BIOS on the Z68 board but that didn't help. I just ran the Intel Processor Diagnostic Tool and it finished up without any errors being found.
I had gotten pretty well ticked off with the MSI boards and went and bought an ASUS MAXIMUS IV EXTREME-Z board and an i5 2500k to run on it if the i7 2600k on the ASUS board went and flaked out like the two MSI boards did. I got to thinking do I really want to chance messing up a very expensive motherboard by even trying the i7 2600k on it.
I'm wondering if I should try running the i5 2500k cpu on the MSI Z68A-GD80 (B3) and see if what I think is a possible bad DIMM slot or if the thing will take off and run just fime with all 16GB of RAM installed. The one thing that worries me is that the i5 2500k could end up with a problem does anyone think I should skip trying the MSI board and just put the i5 2500k on the new ASUS board and forget messing with th MSI board and run it the way it is for a secondary system? Is there any way that the i7 2600 can be tested more than the diagnostic I just ran and if it is safe to install it on the new ASUS board and just run the i5 2500k on the MSI board? I'm at wits end on which way to go. Any suggestions sure would be appreciated.