>None of the manufacturers tend to brag about their 3.3V or 5V >signalling. But they do brag when they have 66Mhz slots. All >the 66Mhz slots are 3.3V signalling by requirement. Many, but >not all of the 3.3V 66Mhz slots on systems can often run at 33Mhz >with 3.3V signalling. Intel Lancewood L440GX motherboard has 32-bit 5V pci slots that runs at 66 MHz.