That's a 440BX board right? If that's the case then the highest officially supported front side bus is 100MHz. P3 933MHz and 1GHz chips run on a 133MHz FSB (well, there were some 100MHz FSB 1GHz P3's, but they were very rare so I doubt you have one of those). You could try overclocking the board's FSB to 133MHz, but I doubt it will run stable at that speed if the option is even available in the BIOS. Plus, back then board manufacturer's didn't lock the PCI and AGP buses, so even if you were able to get the FSB to 133MHz, your PCI bus would be running at 44MHz and the AGP at 88MHz, both beyond what many cards are capable of handling. Your other option would be to run the CPU at a speed lower than what it's rated at.