Recently, on the EVGA forums, I purchased from Chris an I5 3570K CPU.  He took it directly out of a working rig but it will not work for me.  This is really bizarre.  I tried 2 new EVGA Z77 Stingers and a new Gigabyte Z77N mini-ITX.  I get POST error A2 on the Stingers and none of the set ups give anything on the monitor.  Gigabyte mobo gives no errors ( I don't know if it can); just nothing happens.  There are no bent CPU socket pins.  I tried 2 working hard drives.  Multiple SATA 3 and 6 cables.  2 different sets of DDR3 memory in single and dual slots.  2 different power supplies.  Tried with and without a video card.  I am completely stumped.   I wonder if I5 3570K is incompatible with Z77 mini-ITX although it is included in the approved CPU lists.
 
Chris's set up was: 
Asus maximus iv gene-z/gen3 
Dominators platinum 2133
ax750 
asus gtx 660ti
asus xonar essence stx
 
I sent the CPU back to Chris and he re-installed it and it works fine.  Any ideas what to do?  Chris still has the CPU.  Should I ask him to RMA it despite it working in his rig?
Thanks ahead for any help.

jboudwin

Looks like I've got people stumped>

I would have suggested backing the pressure off some on the CPU cooler mounting hardware, but you don't have the CPU to try it?
Can't trouble shoot it when you don't have it!

jboudwin

That's interesting...but on 3 different mobo's?  How would too much pressure affect do that?  I have a new I7 3770K coming tomorrow and will find out how it works in those mobo's.  I still want the I5 3570K for a second rig.  Thanks for the idea.

I hope it works for you! There were some issues with this problem in these forums.

jboudwin

Ok the bizarre continues.  Tried the new I7 3770K CPU and I get the same problem.  Tried easing off of the CPU cooler screws.  Maybe the 600W PSU in the SilverStone SUGO 7 is not compatible?  I've ordered a Corsair 750W PSU and a new case for it.

I am just throwing random ideas at you.
Has this MB been in this case and working at all prior to any hardware changes? No standoffs under the MB in the wrong place (grounding out MB)? All required power connections attached to MB? GPU worked previously or tested in another PC?

It sounds like you may be on the right track with the PSU. Cross your fingers

Fingers are no longer crossed...my eyes are!  Got new PSU today and Z77 Stinger is giving the same A2 POST code error and Gigabyte mobo still does nothing.  Everything is brand new and checks out on other systems.  Even checked hard drive with HD Pro.  I need mini-ITX for my office so I bought an ASUS Z77 micro-ATX to replace my wife's aging out-of-the box HP computer.  I'll try all the hardware on that.  I can't be the only one with a compatibility problem with the Z77 mini-ITX.  This is really strange but I'll keep on trying.

Glad you figured it out, nice find!