I tried installing Core 2 Quad Q9000 CPU to this machine, but the machine will not boot, indicator symbols for Caps Lock etc. on the notification LCD (or whatever it is called) are blinking. I put back the old CPU and the laptop boots. Fujitsu has never offered this model with any kind of Quad Core CPU, but the laptop has GM45 chipset and therefore support for 1066MHz FSB and Penryn. I have read that bios should include support for Quad Cores or the laptop will either refuse to boot or it will boot but just with 2 cores. I already have the latest official bios, but the change log does not mention anything about CPU support so maybe Fujitsu never updated support. Has anyone else tried Quad Core CPU in this or similar laptop and what were the results?