Can X6799A PCI single fiber channel cards be fitted into the top 2 slots of a Sunfire v880. These 2 slots are 66Mhz and X6799A are supposed to be able to connect at this speed.
However , I believe the cards are 5volts , whilst the slots are 3.3volts.
They will be fine in slots 7 and 8, the card in question is dual voltage, it's the QLogic QLA2200F/66-SUN 3.3/5V 32/64Bit 33/66MHz and will work in any of the slots in an 880.