When I am doing research or writing I have Firefox open with multiple tabs running as well as Microsoft Office applications. Within a short period of time, the entire computer slows down. System processes show 100% of CPU used with Firefox eating up about 80%. When I close Firefox and then disable that process, all other programs and computer speed return to normal. I'm only using 1/3 of the available memory. I use Windows 7 and have 3g of physical memory.