Okay, so I have an R9 280x atm and I want more frames! I was just wondering cheaper ways to get higher framerates for a cheaper price and Idk how! Would it be possible for me to get an R9 270x and run them in crossfire? I know that you can crossfire a HD 7970 and a HD 7959, but is a 7950 the same as an R9 270x or an R9 280?
I believe that you can crossfire your current card with the 7950, 7970, 280, or 280x. But the crossfire setup will only be "as good" as the weakest card that you utilise.
You can CF a 270 with a 270X they are both the same architecture. only 270 non X version's have a base clock under 1GHZ X version only means a stock clock from 1GHZ and up.
Anyway you cannot CF a 270X with a 280X, cause thease are 2 totaly diffrent architectures
As far as my knowledge goes not, they are just rebranded 7000 series at least this counts for the 270 and 280 series. The new 280 non X is a 7950. the 280X is a 7970GHZ edition, as far as my knowledge goes you can CF those. But like you said you cannot CF 2 diffrent architectures, like a 270X with a 280X.
But you can CF a 7970 with a 280X for example. only its a bit pointless because your 280x will get clocked down.
The approximate comparisons, from what I understand is:
R9-270 = 7850
R9-270X = 7870 (ghz edition +/-)
R9-280 = 7950
R9-280X = 7970 (ghz edition +/-)
This is not exact, but it's close and should help you figure out where they fit in with the previous GPUs.
I believe you can crossfire as long as it's from the same GPU core family. So for example; an R9-270 can CF with a 270X, 7850 and 7870. An R9-280 can CF with a 280X, 7950 and 7970.
What you can't do is CF any cards from the 270/78XX family with the 280/79XX family of GPUs.
To the OP: what are the specs of the rest of your system and what game or games are you playing (and at what resolution/settings) that you believe you're not getting high enough frame rates with? There might be a bottleneck caused by another part of your system, not allowing your 280X to fully stretch it's legs...
The prices have dropped on the 280x, I just picked one up on amazon for $229 used (A little worried to be honest, but it was a reputable seller and a HIS card) so crossfire should be relatively cheap. At the very least you can pick up a 280x as that is the only other card you can crossfire a 280x with. Overclocking is another option, but these cards are already pushed pretty far so that may only net you 5-10fps at best.