Asus P7P55D deluxe, DIMM A2 and B2 not working

Still searching, can't find any reason why 1 channel won't work. I'm not sure if I have to change any settings in the BIOS to get the rest of this RAM to boot with no BSOD...

I might exchange the motherboard this weekend and get something more reliable seeing how these p7p55d have a lot of posts about them.. If anyone can keep me from making the trip to microcenter feel free to enlighten me in case I'm doing something wrong.

It's not terribly surprising that you can boot with 1 or 2 sticks in A1/B1, but have trouble when you don't put RAM in A1/B1 and instead put it in A2/B2. With 1 or 2 sticks of RAM you are supposed to put them in A1/B1.

Now, once you have more than 2 sticks of RAM you should be able to use 3 or 4 of the slots. However, sometimes you have to up some V or loosen the timings to get 4 sticks working. Have you tried both sets of RAM sticks? In other words, did you test sticks 1 & 2 in A1/B1, and did you test sticks 3 & 4 in A1/B1?

Have you tested 3 sticks?

Yes, I have tested all sets of RAM, they all function in A1/B1, 3 sticks however do not function, no POST.

all 4 sticks, full post, boot up, shortly after boot and operating system loads, (sometimes I can log in) = BSOD

The RAM you have is not ideal for a socket 1156 board (or 1366 for that matter). The latest Intel generation chips have a DRAM "absolute maximum" V spec of 1.65V. According to the link you provided, those RAM sticks are rated at 1.7V and appear to be rated at 1.8V to get them up to 1600 MHz.

If returning the RAM is an option, that might be the simplest route to take.

You could try loosening the timings and setting the V. For instance, set the memory multiplier to 10 (i.e., set the RAM frequency to 1333 MHz). Set the timings to 8-8-8-24 and the DRAM V to 1.65V. If that doesn't work, you could try slowly bumping up the QPI/Vtt (Integrated Memory Controller) V. The typical starting V is 1.1. Bump it up to 1.5. If that doesn't work, try bumping it up .1 at a time, or try 1.2 and if that works slowly decrease it until you find the point where you loose stability. The "absolute max" Vtt according to the Intel spec is 1.21V. http://download.intel.com/design/processor/datashts/322...

thanks for the info, I'll give this a shot

If this hasn't been resolved/ for other searchers, I had the same issue, it apparently is a "Intel Lynnfield CPU integrated memory controller limitation, DIMM slots A1 AND B1 must be populated first, or your system may not boot up, since the memory modules in A2 and B2 will not be recognized. "

http://support.asus.com/faq/asus-faq.aspx?no=89bb904f-c...