Very slow boot of Windows 7 guest on Windows 7 host

[rboettcher]

Dear all,

While setting up two virtual machines on the workstation available in my department, I found that the Windows 7 64bit guest system is booting very slow, especially after Windows updates have been installed. In addition, the overall working speed on the Win 7 guest is quite slow as well (subtle feeling considering what is under the hood). However, the other guest (Linux Mint 12 64bit) shows no such problems.
I recall reading in some previous thread that Windows guests face problems when confronted with multiple cores, but unfortunately I do not know where. Nevertheless, I would like to solve the problem.

Here are the workstation's specifications:
Dell T7500
2x Xeon E5645 (6 cores each, HT enabled)
128 GB RAM (8 GB reserved for host, 60GB are assigned to each VM)
Quadro FX 2000

Any information on how these problems occur and how to speed up the system is greatly appreciated.

Best regards,
René