Why is my Laptop Performance Worse?

Question

I have a Toshiba Satellite Pro LAPTOP with a 900MHz processor (Intel) with 512MB RAM.

I have a Dell Dimension DESKTOP 800 MHz processor with 512 MB RAM.

I am running an engineering application on BOTH of them.

The Dell system will consistently do 850,000 calculations per second.

The Toshiba (with 100MHz more!) will start out at around 850,000 calculations and when I come check on it an hour later has dwindled down to 20k calculations/sec.

After I move the mouse around a little, the Toshiba begins increasing the rate of calculations (very slowly). If I stop the simulation and restart, it again starts off at 850K calculations per second.

This is really annoying. I have the power profile set to never go on standby, never turn off hard disks (ie. act like a desktop computer). Obviously something is not the same. Any ideas why the laptop is behaving like this? Any suggestions? Both are Win2k Pro SP4.

Yes, obviously there are many factors that play into good performance on a system. However the fact remains that the laptop has proven to provide results similar to the PC (ie. in the 850k calc/sec range) so long as I'm there to move the mouse every few minutes. If it were a cache issue, the laptop would not be able to achieve and maintain this performance. I'm certain that the problem lies with the laptop going into some type of "1/10 of use mode" that I'm not aware of. I would appreciate a laptop expert's comments.

Answer 1

People please, The "hype" sold to us, by namely OEM PC Mfrs.10-15 years ago that clock-speed determined the processors performance died years ago!! There are many variables which affect a CPU's overall performance ~ like L2 Cache, The various external busses and controllers generally running at different rates, and the time taken to fetch a datum from memory (read latency) really matters because a CPU will often run out of things to do while waiting for the datum.
When a CPU reaches this state, it is called a stall.