Are you allowed to put expansion cards in it like a modem or a network card? If you can, the PCI video card is no different. When you send the machine back, you just need to remove your PCI video card, enable the onboard video again, and your set to go.
They may not support it if you switch to a PCI video card, but I would be surprised if you couldn't do it. At the very least, if you did something like this (adding a PCI video card), you should be able to take it back out and send it back without them knowing anything about it. The only "gotcha" is if they have some kind of seal that prevents you from opening the case without voiding your lease deal.
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Sean "Lephturn" Conrad - Aces High Chief Trainer
A proud member of the mighty Flying Pigs
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