Hope someone out there can point me in the right direction. I have a Dell XPS 420 system with 4GB 800MHz memory. question is, would it be worth upgrading to 4GB 1066MHz memory which the BIOS tells me the FSB is running at?
No. The cpu fsb may be at 533; this doesn't mean the ram is running at this speed. Cpu and ram fsb aren't the same. Dell systems aren't designed for upgrading. If you want to upgrade, build it yourself.