This board is different from the other 3 P55 boards in that it cannot support 1600MHz, and neither does it support memory requiring > 1.60V. Other people have reported that this particular board is even very picky about the *brand* of memory you use. In summary: this board does not have a very high "memory compatibility" rating.
I do not know the specifics of the memory you are using, but I would definatly look if it is on the official "tested memory" list that Intel has on the support page. If it is not, it may require a (future) BIOS update first. If your memory requires >1.60V beware: that may actually damage the board.
Perhaps you could try to boot the board with totally different memory modules (borrowed from a friend perhaps) and force the BIOS to "forget" any previous memory settings. If the board will not boot anymore with known good modules, you may have bricked it.
Ok....I should have said "no post" instead of "no boot"....no mem installed should still allow the computer to post...right?...the idea being to force the motherboard to reset to default ram settings.
I've been assembling PCs for many years now, and this is the very first time I've set something wrong in the BIOS that I couldn't resolve.
I've learned my lesson. I've been strictly using ASUS and Gigabyte boards, with perfect results, up to now. My only reason for trying out Intel this time was mainly the price. Yah...I shot myself in the foot to save 50 bucks. I'll always swear by Intel processors, but from now on I think I'll steer clear of Intel's motherboards.
Thanks for the insight
My problem is solved, thanks to those who replied to my post for help on this forum.
I had been trying to use some OCZ 1.65V RAM modules, and I apparently set the timings wrong, and got the motherboard stuck at those settings. I was not aware when I bought the RAM that this board did not work well with RAM requiring voltages above 1.6V until someone here told me this. Anyway, I went back and ordered a few G.Skill 1.35V modules, plugged em in, cleared the CMOS, and she booted right up.
So, now I'm not so disillusioned with the Intel motherboads, however, I still think Intel might want to make it a bit more obvious what works and what don't.
Much thanks to those on this forum who pointed me in the right direction!