Install an up-to-date OS. RH9 is extreme legacy. (Ubuntu is my favorite now, and strongly suggested for the newcomer. Read around, others will suggest themselves.)
If by "windows mode" you mean to say that you have installed RH9 in a dual-boot configuration with some flavour of MS windows ... then it is almost certain that the fault is not with RedHat. Be suspicious of the battery or the bios.
If you have some extremely compelling reason to use RH9 (it happens), then you will be faced with massive upgrades. Especially where the battery/power systems are concerned.