I did exactly what you are planing
I use 6 X 22" in a 3 wide, X 2 high array. The 22s are all 1920 x 1080 which 4 of them running off the 2460 card from my main computer. My second machine that runs the other two, 22" displays (is a just a 3Ghz Dual core and it is more than fast enough). There is a bit of neck strain with three 22" monitors side by side (looking back and forth) so I expect 24" might be more than you need, the 22"s wide screens suit me fine. The whole setup (video wise) was around $1K I suppose and has already paid for itself a few times over as you can see 20 - 30 streaming charts all at once (depending on what you are trading). Being able to see so many different markets (forex, commodities, stocks, indexes) as they are all inter-related gives you an edge, there is no doubt about it! I was able to get cheap VESA wall mounts (but still with tilt and swivel for the top row of monitors). Even when a trade goes against you (and if none do then you should be the richest person in the world), you'll understand why a lot quicker and exit sooner before you get stopped out. So even though you're not going to be superman with this setup, even your loosing trades lose less and the winners end up even better as your timing is so much better because you can actually see EVERYTHING. I love it and so does my portfolio. Worth doing at ten times the price.