The second problem is choosing a new GFX card, i like Nvdia but as my current card only supports 2 GFX cards i don't really have the money to go out and upgrade the psu to support another. I have heard from people about AMD cards allowing 3 monitors and only having to use one card. Inside the games, i'm not fussed about the graphics, i just want to be able to play on 3 monitors in the native resolution with a stable fps, even if it means having to run it on low. What card to choose from, i am not sure, i was thinking something similar to my current card. I have done some research into similar cards at a reasonable price:
Two sticks of RAM is definitely a good idea. The monitor isn't one of the best, but if your funds are limited then it's fine. Main problem is I think you're maybe asking too much of these cards... triple monitor gaming is REALLY demanding. It definitely helps that you're happy to use minimum settings and a low resolution, but I think they may still struggle. This is worth a look:
Not the settings or res you're looking at, but just to illustrate how moving from a single display to three displays hurts framerates. GTX690's performance (£750 card) is getting cut in half with three monitors. Like I say though, minimum settings and low resolutions will help... if anyone finds benchmarks for triple screen gaming on low settings, it would certainly be an interesting read.
For comparison by the way, 3x 1440x900 is a similar number of pixels to render as a single 2560x1600 display. But it probably won't be easy finding benchmarking with 2560x1600 combined with low settings. For retailers, these generally offer better prices than Amazon:
Well a 6870 definitely isn't the caliber of card typically used for triple screen gaming, though it may do the job at low settings... I'd personally take a single screen and use the money saved to buy a quality monitor and mid-high end GPU. You also wouldn't then have two big vertical black bars right down your picture :-P If you're really determined to get a triple screen setup though, maybe it would be best to save a bit more and buy something more powerful (and with 2GB).