I bought an SR-X a few years ago to build a system for a buddy but never got around to it until recently. I got all the parts together, Xeon E5-2680 ES CPU's, 48GB of memory, EVGA 970 GTX. The system turns on fine, but sits at the logo screen with a B2 or B4 error code displayed at the bottom right and on the LED on the board. It also say's CMOS Checksun error. Yes, it says "checksun" not checksum. Thinking it was the cmos battery since it sat there for so long, I swapped it out with a new battery and still the same issue. Thinking it might be a problem with the ES CPU microcode, I obtained a retail E5-2620 from a friend to test it with and I still get the same message. Right now, I'm stuck and out of ideas. Any suggestions would be appreciated. Thanks.