What slots do you have available? 4 screen support requires either a display port adapter, or two cards, the second option is the cheapest if you have the space for it. You can run two cards independently(not CF/SLI) and they can each support their full compliment of monitors, so you could get 2 5450s for a total of $66 and have 4 screen support for less than a card that can do 4 screens by itself
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