Sometime when I restart Windows 7, my system will show the shutting down message and then a blank screen for about 20 seconds and then shutdown instead of restarting. Sometimes I have to press the power button but one time it turned back on itself a few seconds after shutdown. I changed the command rate from Auto (1T) to 2T and now it seems like that problem has been resolved. My memory does not define what command rate it should be running at for the non-XMP setting under the Tool feature in the BIOS but I know that 2T is more stable the 1T. Otherwise it's still running at advertised settings without problems, so far. Memtest ran fine for 5.5 hours at 1T and so did Intel Burn Test and the Windows Memory Diagnostics so I'm not sure if it was an issue with the 1T command rate or just a bug in Windows 7. I didn't have this issue with my previous memory but my previous memory I ran at 2T command rate as that was what was defined in the XMP settings of my old memory to get 1600 speed. Does it sound like it was the command rate which was causing the issue with shutting down instead of restarting?