Maximus IV Extreme-Z won't recognize RAM in Dimms B1 or B2

Silly me i7-2600K processor...

try using a2+b2 and a1+b1 and see if it works

and did you change your stock cpu cooler?if yes then if the cooler has a backplate, on the backplate,insert four nylon/silicon washers (Maplins) on each screw. to stop backplate from making any metal to metal contact with the motherboard.

A2/B2 no good. Still need to try A1/B1.

Stock cooler (for now). Tried CM 212 Evo, but memory would fit under it.

did a1/b1 work?

i`m having a similar problem:

Asus Maximus V Gene mAtx
Corsair DDR3-1866 4 x 4GB (matched)
i5-3570K

if i populate DIMM A1 or A2, it won`t post. Gives error 55 - memory.
if i populate B1, or B2, or B1+B2, then it posts and loads windows no problem.

I`ve tried testing all four in different configurations, and if A1 or A2 are used, it just won`t post.
I`ve flashed the latest BIOS (1101, if i recall correctly), made sure all DIMM are enabled in BIOS, reseated all memory and the CPU and the stock cooler, tried manually setting the RAM to DDR3-1333 1.5v, and gone through an arcane ritual of CMOS CLRs, «BIOS loads, power downs, and resets to appease the machine god, but no luck.

Its very perplexing.

There seems to be some uncertainly on various forums whether its the fault of the BIOS, an aftermarket cooler affecting the CPU by being tightened down too much, the RAM, or the mobo. I`m kind of at a loss... I don`t know if RMAìng the mobo would even fix the issue! So instead of 16gb of dual channel, I`m running 8gb single channel. boo urns.

I`d cross post this on the Asus ROG forum, but it seems to be down.

trip, did you ever find a solution for this? I'm having the same exact issue.

I want to get it working so I can get some sleep!

actually, dude, i DID solve this   I thought i had followed up on all my tech forums when i was problem-solving this, but obviously not....

let me cut and paste from my post on the AsusTek forum:

Before I boxed up my motherboard for an RMA situation, I took another close look at my land grid. It all seemed normal. I flipped over the CPU itself, and looked at the contacts, making sure each one had a small indentation in the centre from the corresponding pin in the socket itself. And lo, one pin along the outside perimeter did not quite line up in the center. I looked back at the socket, identified the pin, and it was indeed a mm or so off.

20 minutes with a sewing needle and a magnifying glass, and I had brought the pin back to center. Seated my CPU again, locked it down, loaded up all 4 DIMMS, and it booted up, no more problems.  

Hope this helps with your issue, as well!

I just had to register just to thank you, triptyck. I had almost lost faith in ever solving the issue but then found this thread. However I had a little different approach. I took a photo of the socket and by zooming in the photo was able to check each pin. Bragging: I used only a lamp and a needle as I didn't have a magnifying glass. I was quite lucky and it was all good in the end. Everything runs smoothly now.

Thanks again!

Edit: typo