So I have an MSI Radeon HD 7770 (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) and I've been thinking about upgrading since I have a bit of a choke in performance in more modern games like Crysis 2, where I can only hit medium-high graphics. So the question is, should I go for a second 7770 or buy a brand new 7870?
It's always recommended going with a single better card in those cases, it's not good to crossfire two 7770.
It would be more valid if it were two 7850/7870 or a 660/660 ti.
In my opinion you should get the 7870.
While I agree with you, I am a bit tight for money right now, so getting a 7770 seemed like a decent idea. Yes I know it isn't future proof, but benchmarks show that they can perform sometimes just as well as a gtx 580, which is something which can't be ignored.
I can't say for the performance of two 7770, but i don't think they will be much better than a 7870.
And there's the cons of two low end cards, micro stuttering, without driver support a single card isn't enough for 1080p(in some games).
Since u already have a 7770, id say go for crossfire as what im doing with my 6770, i got another one since i didnt have the money to get a nice single card, except i bought both my gpus used for like $50 a piece lol
U could always try to craigslist or ebay the card and see how much u get from it, and get a 7870 or 7850, if u have the money for a new 7770 at 135, then getting $100 for the current one will be enough to get a 7870 or 7850. If u had the 2gb 7770 that only asus sells u prob could just get another since maybe ur lacking vram im not sure but there $160 a piece.
So ur decision on getting another card to crossfire, or sell ur current and get a good single gpu, Xfire 7770 are very similar to 7870 in bf3 performance, but Xfire in crysis 2 on ultra 1080p is about 20fps less than one 7870
i would go a faster single card any day of the week over a mid range crossfire setup. You will have much smoother gameplay with the single card. Crossfire is best left for high end systems where 1 card is not enough, and has enough power to avoid fps drops and stuttering like the midrange cards have in crossfire. Also the lack of the 7770's vram is a problem in newer games.
While crossfire is never as trouble free as the same power in a single card, in the last year AMD has done a very good job of getting crossfire issues in check with driver updates.
If you can save a bunch of money using crossfire, I say go for it!