"ASUS P5Q Deluxe discussion".

[CryptiK]

im on a plain P5Q.
i easily run 499fsb 5:6 1199ddr CL555-15 PL9 on only 2.1v 24/7 prime blend stable for hours on end, OCCT stable, memtest86+ stable for hours on end including just looping test #7 for hours on end, etc.

but it wont even post @ 500/1200 CL555-18 PL10

dropping down to 1:1 i can post and bench upto 540/1080.

tried Ket's m1306, didnt fix it.

That is EXACTLY what my board does. Rock stable at 499/1199 but as soon as I go to do 500/1200 i get black screen and no post. Damn annoying isn't it? I'm RMA'ing my board because of it. Says on the box my board can do DDR1200, but no way in hell will it do it, no matter what divider or FSB or strap or bios version I use. It has driven me insane.

Oh and I have 4 kits of ram that all do DDR1300+ so it's not them, definitely the board.

EDIT - only difference between you and I is I can load windows and bench at 590 FSB 1:1.