99% CPU on M6400 (with A09) after upgrade to Windows 7

Have a M6400, with Core 2 Duo T9600 @ 2.8GHz, which was delivered with Windows Vista (64-bit), and BIOS revision A03.

After upgrading to Windows 7, I've been experiencing problems that make the system practically unusable.

One of them, which I believe I fixed, I'm mentioning just in case it might prove useful to somebody else. The system froze completely when downloading big files in the browser (Firefox), or working with large mailboxes with Thunderbird. Apart of correlating it with disk activity myself, at some point I was able to reproduce a crash (BSOD) with a stop code (0x00000096), which led to a page that was suggesting updating Intel's Matrix Storage Driver. Windows itself thought that it was running with the latest version, however the really latest version is available on both Intel's and Dell's pages, and after a week without a freeze, I believe this is now resolved.

Second, and most important, and as the subject already indicates, the inexplicably high-load that makes the system unusable. During various attempts to diagnose, I've noticed that in safe-mode this was not coming up, so I've disabled all services that were not running in safe-mode. A similar plan involving drivers was abandoned, since disabling the services was enough for the thing to go away.

After a week of gradually re-enabling services (1 or 2 per day, out of a total of 45 to go), the problem comes up again. However, now I've been able to also observe the following:

* its occurrence is independent of the group of running services

* when it comes up, it persists even after rebooting the system

* the heavier the activity on the system, the sooner it occurs.

* when it comes up, the part over the keyboard is *really* hot.

So, my most recent diagnosis is that the system somehow gets very easily hot, and then it throotles itself so much that it becomes unusable, and there's also some evidence to this:

* CPU-Z shows that the processor is running @ 900MHz, when it comes up

* it goes away, when you let the laptop go cool, and start it up again

My concerns/problems/questions right now are these:

1) CPU-Z pretty often shows the processor running at 2929.5MHz. Since usually nominal speed is the real maximum rounded-up, I'd expect that a 2.8GHz runs below this frequency, rather than above (even when it the difference is so small).

2) Isn't it unusual, that only services and some very low activity is enough to make the system burn, and trigger processor throttling?

3) According to the blog-entry titled "Dell on Laptop and Throttling" (sorry, but I'm unable to create a link from my browser), revision A09 of the BIOS was supposed to solve this very problem (which BTW, I did not have with Vista, but do so now with 7).