The January and February Quality and Security Windows 7 Updates have caused a Restart issue on Sandy and Ivy Bridge processors.
My customer's Z210 has a i7-2600 processor. After KB4056894 was installed the PC hangs on restart about 60% of the time. The symptoms are black screen about the time that you'd expect to see the HP logo. The keyboard is inactive, no mouse cursor, fans running and power light on.
Removing KB4056894 resolves the restart issue. Others have found that the Feburary updates cause the same problem.
Some people have had success by disabling the C6 or C6 Report power states in their BIOS.
I've attempted to find those power state controls in later model HP Workstation bios setting but have not found them.
I'm hoping that someone can tell if those controls exist in the Z210 bios and if so how to find them.
Thanks,,, Dave