As long as the mains is plugged in and as long as you don't have a power failure you should be alright to flash your bios. However I very much doubt it will help that much with any problems you are having with Sims 3.
As long as the mains is plugged in and as long as you don't have a power failure you should be alright to flash your bios. However I very much doubt it will help that much with any problems you are having with Sims 3.