New processor not POSTing

I'm helping a friend upgrade his desktop - or I thought I was. We've bought a Thermaltake TR2 500W PSU, 2x4GB Patriot 1600MHz RAM, Gigabyte 970A-D3 mobo, and AMD FX-6100 CPU. I get fans on, black screen, no POST beep. I tried it barebones, no go. I tried it with my Phenom II 955, and the system works. That might lead me to think that the processor was bad, except I've exchanged it at Fry's four times now. I was reminded that many boards needed to have the BIOS updated for AM3+ processors, but I discovered that this already had version F6. I put in my old processor and flashed the BIOS to F7 anyway - no help, of course. I also tried clearing the CMOS after putting the FX back in.

Any other ideas?

Is it old installation?

Windows 7, though while I've been debugging this the hard drives haven't even been plugged in.

I unfortunately do not have another AM3+ board with which to test the 6100. I don't think all five 6100's I've tried would be bad. Also, I assume the PSU is good because the system will boot with an older processor in it.

Sorry, I thought your post said 4 different mobos. I'd try a different one then whatever you've tried so far.

Better chip anyways, I'd keep that one.