A few weeks ago I reported that I'd put together a PC with my kids and it failed to start up. After trying a variety of things, I came to the conclusion it was the motherboard, the CPU, or RAM. A friend sent a note to say he had a couple of sticks of extra RAM I could try in it, so after a week of forgetting about it, I finally did and it solved the problem!
The new RAM was from Silicon Mountain. The RAM that wasn't working in the motherboard was Kensington. Various forum postings indicated that the RAM settings in the ASUS motherboard could be problematic. I tried changing them to the recommended settings with the Silicon Mountain RAM in place (so I could even run the BIOS) and then using the Kensington RAM, but that made no difference.
Interesting that they're playing it so close to the edge on timings, but I guess that's the name of the game in high performance systems. In any event, I just bought some Silicon Mountain RAM and gave the Kensington RAM to a friend. Hopefully it can be put to good use somewhere else.