I have a Z600, Boot Block 1/30/09, running a generic Windows 7 x64 operating system. I just upgraded the machine from an E5520 to dual X5570 processors. The Z600 boots without any problem. However, if I activate hyperthreading in the bios, the Z600 hangs on boot.
Upon reboot, the Z600 hangs at the exact same spot (when the Windows starting is displayed).
Upon failure (with hyperthreading enabled), I've run startup repair and it says it cannot fix the problem. The problem signatures are 6.1.7600.16385 and 21198350.
I ran Intel diagnostics and the computer passed all the tests.
The exact same errors and behavior occur every time hyperthreading is enabled.
As soon as I disable the hyperthreading, the computer starts just fine.
I'm obviously missing something... Any suggestions are certainly welcome! Fortunately, I'm happy to use the 8 cores... I'm just a bit curious about what I've missed.
Thanks!