I need a GPU solution for four 17 inch screens. It's not a gaming rig and the screens will only be showing graphs and charts so it doesn't need to be expensive but it has to have four monitor outputs.
A single card with four monitor outputs? Or two cards with two outputs? the latter will be easier than the former, but depending on the monitors being used, you can get any of the AMD cards that support Eyefinity (Eyefinity Editions) that use the Mini Display Port plug to make it work. A couple of examples:
Outside of that, you can try to fill the PCIe slots with lower end cards that have just one display port, or you can find a lower end card that offers two ports per card (and buy two cards)
So you have tons of options either way.
if you want to go the dual card route and don't care about games, you can buy a couple of these:
and throw them in any of the PCIe slots (since PCIe isn't limited by connector size - if it fits, it'll work) then just use the combination of the ports (probably DVI, DVI, VGA, VGA or any combination of the DVI, HDMI slots as necessary)