How can i set up quad monitors

its not for gaming but for stock charts and online trading.

these cards are supposed to run 4 monitors
would they be a better solution.
certainly would leave more slots open on the motherboard and take less power.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814139049R

http://www.newegg.com/Product/Product.aspx?Item=N82E16814139037R

http://www.newegg.com/Product/Product.aspx?Item=N82E16814139047R

The only problem i see with these is that all the monitors must either be dvi or vga depending on the card. no mix and match.

is there any kind of adapter to make a dvi into a vga or vice versa?

or any other solutions for a 4 display system?