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We're doing some remodeling in some of our offices here and apart of it, one of the conference rooms will receive 4 lcd tv's and the goal is to run them via a PC to display company data.

So, I've designed a PC at newegg - i7, 8gb ram, etc... going with a Radeon 4670 with quad DVI out

Wanting to see what I want to show on the 4 tv's on the wall, before putting the data up on the wall, I've opted for a 2nd video card, Radeon 5450, that I'll connect to a monitor on the desk. That'll be the primary monitor, and they can drag the data windows up to the TV's and everyone will be happy.

My concern before i check out is, I've chosen a Asus P7P55D-E - and although it has 2 pci express 2.0 slots, the speck says if both are used, they run at 8x each (not 16x)

Does this work? can a 16x card work as a 8x card? Should i look for a motherboard that can do 2 pci express 2 slots, both at 16x each?

No gaming on this box - excel sheets, pdf's, iSeries Access, etc... max video usage will be power point presentations.



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Yes, any slot can downclock - you can use dual x16 cards fine and they will run at 8x. You can probably find a board that supports 16x/16x but it'll be more expensive due to an extra chip needed, and the performance difference between 8x and 16x on the kind of workload you describe with a card like that is about 1% or less (basically, not worth the expense).

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We constantly answer the same questions at the same time lol :). +1 for you. – Not Kyle stop stalking me Mar 1 '11 at 18:31

You can run any speed PCIE card in a 16x slot they are fully backwards compatible. For example a 1x card will work in a 4x, 8x, and 16x slot. Keep in mind there are no physical differences between 8x and 16x slots it is only the number of lanes that are available for the cards to talk to the CPU. Judging by what you are planning to do here two 16x cards running at 8x are going to be just fine.

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Ditto on the timing ;) – Shinrai Mar 1 '11 at 19:22

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