Kernel level execution of program to change CPU clock rate?

enguy · 11-30-2005, 05:08 AM

Would I be able to change the CPU speed while using any low-level assembly program? It need not be running under Windows....

Will.Spencer · 11-30-2005, 09:00 AM

I do not believe so, on most modern machines.

For several years, programs to slow down PC's were popular. This was so that people could play games designed for 4.77Mhz 8088 CPU's on their brand new 8 and 10Mhz machines.

Those programs worked, as I recall, by executing a small and tight loop in the background. The CPU wasn't really slower, it was just busier.

Modern PC's control the speed of the CPU using jumpers or DIP switches on the motherboard or settings in the system BIOS.

You can poke new values into the system BIOS settings -- but I do not know if they will take effect before the next reboot.

enguy · 11-30-2005, 09:27 AM

Oh! Thanks for the clear cut message. I would stop my further attempts on those lines. I just wanted to do something really stupid for my embedded systems coursework.