I have a BFG 260 nvidia that works fairly well, but want to get a drool machine. I know everything I want except video card wise. I will eventually get four but was wondering if just getting 4 5770s right off the bat would be better than just getting one 5870 and then slowly getting the other 3 over the next 7-8 months? Also recommendations on what to get if I go either way 5770 or 5870. Asus doesn't look that good unless I go 230 dollars or more.
4 5770s isnt going to perform well at all, scaling drops dramatically as you add more cards so 4 5770s would end up giving you about 1.5x the frames of a single 5870. Most boards cant even support 4 dual slot GPUs, normally the only way to pull of quadfire or quadSLI is to use dual GPU cards like the 5970 and GTX 295.
SLI does scale a bit better than crossfire so if you are going to do a 3 card config in the future i would suggest going for GTX 480s to get the most power, just make sure you have a large high quality PSU to feed them.
As hunter said, it isn't exactly going to scale well.. However i actually have to disagree with the GTX 480 recommendation. They are 100$ more than the 5870's use more power and hardly run "cool". Sure the 5870's don't exactly run super cool, but they sure as hell run cooler than the 480's by a mile when OC'd and running load. Also, i find that another 5870 plus is that they actually have low priced non-reference cooling. For instance the HIS iCooler V Turbo.
Neither the GTX 480 nor the HD5870 are wise purchases. The HD5850 and GTX 470 are both much better values for the money. The cheaper cards OC to the same levels as the more expensive ones and at that point the performance difference is minimal(5-10%) compared to the large(33-50%) price difference.
SLI tends to scale better than crossfire so I would go for 2 GTX 470s which will cost the same as the 4 HD5770s you are talking about(about $600.) At stock the are superior to an HD5970 and the can OC a very large amount(35-40%.) Keep in mind they do use a lot of power/give off a lot of heat so you will want a good PSU and a case with good airflow.
Thanks to everyone, especially jyjjy. I like the cheaper price tag. I can understand the dual 470 set up and it would still allow me to keep my 260 for a physx setup. That is really good. I do intend to get a 1000 watt psu possibly a Corsair Gold AX1200 if I can afford it. Got a good case and 5 fans running full blast. Just don't know if I want water cooling or not it still is to risky imo.