Gtx 580 SLI vs single gtx 660 ti

gtx 580 sli is much better than single gtx 660.

Two 580 would definitely perform better than a 660ti if SLI scales accordingly. Don't get a 660ti, you'll only see little improvements from a 580. I suggest you sell the 580, and get either a GTX670 or Radeon HD7970 to see some worthwhile purchase

yes two 580's will perform much better. A 660ti is on par with a 580, so getting it will be a waste on money. Hopefully you have a mobo that supports sli and a psu powerful enough to run two cards. Would not be worth it if you have to get a new mobo and new psu as well. If that is the case. Sell your gtx 580 and get a radeon 7970 ghz edition as EzioAs recommended. (Getting a gtx 670 would only be a small improvement and wouldnt be worth it.)

The reason why I never recommended the 7970GHz is because a standard 7970 can hit 1000MHz easy. I know most people would pay for factory overclocked cards but I would rather get the standard 7970 and overclock it (which in most cases will hit around 1200MHz on core clock)

I'd like to have a 3d setup, can the new card have more memory than the other one or do they have to be the same if I were to go with sli?

If it's in multi-gpu config, you'll only get as much as the lowest memory available on the cards (ie. if you have 1GB and 2GB cards in crossfire/SLI, you'll only get 1GB available). I could be wrong on this though.

í think u'll get full memory anyway what's ur PSU type u should have atleast 750 W PSU for handling GTX 580 in SLI , and yes 580 sli is much better than a 660 ti and even better than a 680 , however if u don't really like to cook on r Rig u should then go for a sngle 680 which will give a very good performance too  

I've confirmed this. In crossfire, he'll only get the lowest out of the 2. On the other hand, it seems like SLI won't work with different amount of VRAM

i really wasn't sure about my answer but yes u r correct he'll get the lowest memory however this won't affect him too much the main important thing in SLI is the sharing between 2 GPUs not the VRAM

Would you guys say that my current 1000w power supply is enough?

In case you need to know the rest of my specs area as follows:

Phenom 1090t x6 OC'd @ 3.9 GHz
EVGA GTX 580 1.5GB
16 GB corsair vengence RAM
Asus Formula V Motherboard
1TB HDD (cant remember the brand)
1000w PSU
120 mm case fans x2
200 mm case fan x1

If that psu is a high quality unit, you can do 3-way 580 no problem. Can you give us the psu specific model.

It's the Coolermaster Silent Pro 1000w, here's the link http://www.coolermaster-usa.com/product.php?product_id=...

Yeah, you can do 2 580 without any problems.

Nice ! this PSU would handle both without any problems  

Thanks a lot man, I'll hit the shops soon!

If you connect 2 GPU 580 your CPU will bottleneck. I had same CPU in 4,0GHz and two Asus GTX580 DirectCUII SLI and this card worked at 60°C. I change CPU on i5 2500K in 4,6GHz and temperatures on GPU are 85°C(up) and 83°C(down).

Id sell the 1 gtx 580 you have and for what you will get for it you would probabaly get a 7950 for next to nothing.Then spend another $300 for a second one since your going to be spending close to that on another gtx 580 anyways.

the 1.5gb vram will start to become a limitation in the gtx580 with some new and future games, you will have to compromise by turning down AA and texture detail a step down from its highest setting. So i think selling it and getting a better single card would be better than going SLI. Also CPU bottleneck with the AMD cpu.

I agree 1,5GB VRAM is little