I have a Asus A8n-sli premium mobo which has 2 PCIe x16 slots, 1 PCIe x1, 1 PCIe x4, and 3 PCI slots. Need a cheap fanless video card so I can remove the noisy Geforce 7800GT. Any recommendations?

Here's one:

 

http://www.newegg.com/Product/Product.aspx?Item=N82E16814143098

 

It doesn't matter what you use.  Any video card will do.  You only need a video card to display the bootup info. 

That is an AGP card.  The one I purchased from Newegg a few weeks ago for $35 was this one: http://www.newegg.com/product/product.asp?item=N82E16814127243. It is a PCI Express x16 fanless GeForce 7100GS card, worked without a problem.  Unfortunately!, Newegg shows it as out of stock, expected next June 6, but perhaps someone else will have it.

 

Newegg does show about 4 or 5 other PCI and PCI Express cards for $33 to $35, Radeon 7000's or GeForce 6200's.