I have a P4 3.8GHZ with 1mb cache 800 MHZ FSB 2GB DDR2 533mhz RAM 256 MB ATI X850XT PE 460 Watt Power supply 10,000 RPM 74 GB Drive 500 GB 7,200 SATA2 drive Running Windows XP Pro I want to upgrade it to 4GB DDR2 800 MHZ RAM ATI HD 4850 512MB (I heard 1GB is not really needed) Windows 7 Home premium Can't do the CPU due to Dell using custom Motherboards. Is it worth my trouble to do this, I am thinking that the memory size and speed will stop that bottle neck and the GPU upgrade would help alot. I am looking to play Fallout 3 and Boarderlands on quite high settings.

check your system manual for memory and cpu support, and its time to upgrade vga card hd 4850 is a good card.

I know the cpu cannot be changed and that 800MHZ DDR2 is supported, Did ATI fix the fan problem on the 4850's I heard it was a driver issue?

"I know the cpu cannot be changed" The reason it can't be upgraded is because there's no P4 that runs faster than 3.8GHz. Your board *may* accept a dual core CPU, but you didn't bother to list the model number so there's no way to check. http://www.intel.com/pressroom/kits... "I want to upgrade it to 4GB DDR2 800 MHZ RAM" DDR2-533 is the correct RAM to run with an 800MHz FSB P4. It provides a CPU:DRAM ratio of 3:4 which is considered optimal for a P4 & it's crappy netburst architecture. Best Graphics Cards For The Money: November '09