Please note that different bios revisions may give different results. All benches are done with AUTO settings, without altering any BIOS option besides CPU VCore and major CL settings. DDR3 speed is always 1066MHz or as near to 1066MHz as possible.

Cinebench R10:

QX6850@3000MHz:


QX9650@3000MHz:


QX9650@4000MHz:


As you can clearly see the QX9650 is 7.5 percent faster. The bigger cache does not count for this increase, we believe that is caused by support for SSE4.