[Tfug] Got an odd one: laptop AMD CPU stuck at 800mhz, won't jump to 1, 600

[Jim March]

Folks,

Somebody gave me a Dell Latitude D531, has an AMD CPU (dual-core
TL-50) that can "speedstep" between 800mHz and 1.6gHz.

I dropped my existing hard disk from another laptop over to it, fired
it up.  Existing install is Mint 12, 32bit (similar to Ubuntu
Oneiric).

Seemed ghastly slow on the "new" machine.  I noticed that my CPU
frequency scaling toolbar thingie that I always run showed it locked
to 800mHz.  This tool can also show available speeds and if you want,
lock the CPU to one speed or another.

It would not accept a command to crank it up to 1.6.  Literally wouldn't take.

I tried turning off Speedstep in the BIOS, locking it to high speed.
No joy - the frequency scaler broke at that point but performance
testing of, say, flash videos (plus slow boot times and more) showed
the speed was still stinking.

OK, what the hell?

Has anybody seen anything like this before?

I'm going to try swapping the RAM over (2gig PC5300 on both my old and
this "new" lappy) and see if that helps?  But...I don't think that's
it.

What would cause the CPU to be locked into stupid mode?

What else...video card on the old machine (physically falling apart!)
is an Intel 965/X3100 type, new (the "slow machine") is an ATI 1270.
The ATI video drivers seem to be working OK (open source Radeon).

Jim