GPU advice: 1 or 2?

[StBishop]

Ok so my GPU is dying. My screen regularly freezes and blacks out then comes back with a helpful tooltip saying that my driver stopped working and that it's been recovered by windows.

This thing is ancient (I updated the driver and the date on it was like 2008) it's the only part of my PC which is older than 10 months and I finally have some money to update it.

So, I have a couple of options, but first, what I want from my PC.

I want to be able to run a couple of programs at once without performance issues (ie. Chrome with about 20 tabs, iTunes, Excel, Word, and about 5-20 PDF files open in Adobe) as I mostly do research and assignments on this computer.

I'd like to be able to run dual screens to that I can read and write without "alt+tab"ing constantly.

I'd like to be able to run LoL. I don't really play any other games on PC, all of my triple A gaming is on console.

I'd like to be able to keep this card until about 2014.

My budget is about $100-$200 Australian Dollars. Because I'm a broke student who's only got one textbook to buy this semester and I get a scholarship so I have a little to spare.

With that in mind I have a few specific cards in mind.
One of these: EVGA GTX550 TI FPB 1gb

Or Two of these: XFX HD 6570 1gb in crossfire (but I believe this is almost useless for my needs as I won't be doing much which will use the cross fire's potential or some nonsense).

I'm also open to suggestions. I would prefer to buy something from either: PLE, Austin Computers, PC Case gear, or another Aussie site/Perth store.

So, thoughts?

EDIT: Not a single opinion? Strange.

 

[ohnoitsabear]

Using two graphics cards is really only a good idea if you're upgrading a build that already has one decent or better graphics card. So in your situation I would say go with the single graphics card.

As far as the card you picked out (the 550 Ti), it's certaintly fine for what you would be doing with it, although if you think that you might want to play games other than LoL on your computer, you would benefit from getting a slightly better card (maybe a 560 Ti), but I wouldn't do it for just LoL. This is something you would have to decide for yourself.