Saw this about the DQ6 on silentpcreview.com :
"I initially tried the DQ6 motherboard, but it was not a happy experience. The 965P north bridge actually has fewer features than the 945P on my old motherboard, and would not allow me to directly control the DRAM parameters. Also the BIOS is set up for overvolting and overclocking only; it is not possible to set voltages directly, or below the stock values called for by the VID and SPD."
I'm not an OC'er yet so that's all jarble to me lol. But sounds like it's lacking a lot of OC'ing features. That was with an e6600 though, so might be different for the e6400?