Don't get hung up on SPD. No DDR3 memory manufacturer has got their SPDs correct for other than default settings. Remember, the only thing SPD does is set the default timings.

pojo: Because you have a q6600 the board is going to default to it's FSB which is 1066. Don't make any changes from the defaults except voltage. If you can't get that stable then there's another problem. Make sure you're running Memtest86+ v1.70 and run test 7 specifically. It's the only test that even comes close to simulating the stress that windows puts on memory.