To change the performance of foreground and background programs
Open System in Control Panel.
On the Advanced tab, under Performance, click Settings.
On the Advanced tab, under Processor scheduling, do one of the following:
Click Programs to assign more processor resources to the foreground program than the background program
Click Background services to assign equal amounts of processor resources to all programs.
To open System, click Start, click Control Panel, click Performance and Maintenance, and then click System.
Choosing the Programs option will result in a smoother, faster response time for your foreground program. If you want a background task, such as a Backup utility, to run faster, choose the Background services option.
The Programs option allocates short, variable time slices, or quanta, to running programs, while the Background services option assigns long, fixed quanta.