I just got an Intel SSD 520 and already I'm having problems. Even during Windows installation, the HDD light will stay solid and the whole system will lock up, then about a minute or so later, everything is as if nothing happened. I did a full diagnostic scan with the Intel Utility, and nothing looks abnormal, however, the unsafe shutdown count is now at 32 (from the SSD locking up I assume) What could be causing this?

Another question I had, I have the latest Lenovo BIOS flashed, does this support the SATA II speeds? When was the last time the Midldeton BIOS has been updated? Am I best off staying with what I have?

EDIT: I noticed that the system locks up more frequently when the SSD is under heavy use or when I put an HDD in tel ultrabay

I ran this SSD in my T61p for months with no issue using Middleton's BIOS.

Lenovo's latest BIOS is NOT SATA-II enabled. Middleton's IS SATA-II enabled.

As I recall, Lenovo does have one newer BIOS version available but it doesn't contain anything compelling according to the changelog.

Get Middleton's bios for your machine here.

Once you've got that installed, report back... perhaps your SSD is defective?