When I said flat I actually meant those that are about 2 inches thick. From front to back. VGA monitors are usually about a 12 inches or more front to back. My VGA monitors have flat screens but are 12 inches+ from front to back.
Why don't you give those people a call at the website I posted. Explain just what you need and see what they say.
Tell them you've got 2 more vid cards to add when you get it.
Now that I've thought about it, could be an alright deal to get it from them.
BTW, don't go for the cheapest mobo, the mobo is the heart of the system. So I'd avoid ECS mobo's and go for either ASUS, GIGABYTE, or MSI. With those brands even their cheap mobos are as quality as their expensive ones but with less features. There's other good brands but those are what NEOCOMPUTERS offers.
(ABIT's might be good but I'm not familiar with them)