I am assuming that you have bios 203 or higher. Somewhere along the line...the techs who write the bios have handed us an interesting situation. My believe, as many others on the Asus boards, is that the bios overvolts the memory. I have Crucial Ballistix Tracers PC8500 and would receive numerous memory errors in Memtest In order to alleviate the errors while running bios 501, I had to volt the memory manually to 1.85v. Now this works..in my case, but I found another solution...listed here on the Asus boards page 4. Mine is second to the last on the page...read the whole page and get a gist of the situation. You are NOT alone!
You can backflash the board's bios...very tricky and using an older version of Asus Flash. It works, however. I am currently running bios 107 on my motherboard and my memory is volted at 2.2 and I get 0 errors...even after having run Memtest for 6 hours. First try manually turning the voltage of your memory down until the errors stop. If you are within 1.8-2.2v...you are within JEDEC standards. If you want to flash to bios 107...it can also be found on the support section of the Asus website under your motherboard.
I used to have that same memory on an Asus Maximus Formula SE. As yellowbeard said you probably need to set the memory voltage manually. When I left the voltage on auto it was only giving my memory 1.95V or so. Then when I set it to 2.10V it was overvolting it to 2.14V so I had to set the bios to 2.06V to get the proper voltage. Use PC probe or something to make sure you're giving your ram too much juice.
Set AI utility to manual
Set ram settings to manual...then 1066 mhz
Set the CAS, etc to Auto...the board should recognize 5-5-5-15
Set voltage (highlight with up/down key...hit enter and type in 1.90v)
Save and reboot...see if that makes a difference. My suspicion is that the bios overvolts pretty heavily and on your P5B deluxe...it doesn't. When the ram is volted properly...it does work. On my P5E, before I backflashed to bios 107...I was running my Crucial Ballistix Tracer ram at 1066 mhz and volted at 1.85 and it was rock solid...but after backflashing...I am in great fear of flashing again. Just can't trust that the board will survive many more. Waiting for the bios that allows the new .45nm Quad processors...then I'll flash...and if it dies...I'll go with a Gigabyte or MSI motherboard. Asus is really letting this board get away from them...