Hi all,
Just a quick experiment which I had chance to try that I thought may be worth sharing.
A question that I have pondered and im sure many others have is "Should I sell my current GPU and upgrade to a new one, or buy a second card to Crossfire/SLI instead?"
This question was a little academic for me as my ITX board only supported a single card, which led me to upgrade to a new GTX 970 from my older HD7950.
However, I am currently building another PC for a friend and the opportunity came up to try and answer this question using 2x HD7950s vs the GTX 970.
So with out further ado here are the specs of the hardware I used and results of some bench tests:
Motherboard - Gigabyte Z77X-D3H
CPU - Intel I5 3570K @ stock clocks (with 3.8ghz turbo)
CM Hyper 212 CPU Cooler
8GB Ram (1333ghz)
40GB HDD
Enermax Platimax 500W PSU
Corsair CX500W PSU (had to use 2 x PSUs for crossfire setup)
(All the benchmark programmes I used are the free download versions so are all the basic bench tests)
The first Benchmark I tested with was Unigene Heaven, I also used a single HD7950 for comparison to see what the gain may be when crossfiring.
As you can see adding a second HD7950 almost doubled the result, and gave an improvement over the single GTX 970
Next was 3DMark 11
The crossfire setup stretched ahead again but only marginally compared to the GTX970, though this was for the overall P score.
Looking just at the graphics score, the gap over the 970 increased again, and once more almost doubled that of the single card
Finally I tried the test using the Catzilla Bench test
Here you see the GTX 970 leaps far ahead of the HD7950, with the Crossfire set-up actually scoring less than the single card.
This benchmark was obviously not compatible with my crossfire set-up, which is always the Achillies heel of dual graphics cards, not always being supported in all benchmarks and of course games.
So did I answer my question?
Yes, for me at least.
The GTX 970 came in at around £50 more than it would have cost me to keep my old card and to buy a second HD7950.
I do not play a large variety of games, and although I did not get to try the set-up on the games I play, I do know that crossfire is compatible and likely to give a better performance than the GTX970.
Having said that, to upgrade to a crossfire set-up I would have had to have changed my motherboard, case and upgraded my PSU, in addition my electricity bill would also have taken a not so insignificant hit, so for me the choice I originally made was the right one, the GTX970.
Obviously the answer to this question may be different to someone else who already has a compatible motherboard and PSU, but I would advise to search the web to see if the games you play are compatible, and of course remember future games may not be, or least may take some time until they are Crossfire/SLI ready. Another note worth a mention is future Direct X and Mantle compatability for older gen cards may also eventually become an issue.
It is however tempting to try, and you can get mega gains for not such a massive outlay on the right games/bench tests.
I hope you found this little test of some interest and maybe even of a little help.
But at the end of the day, the choice as "Our Graham" used to say, is yours.
Thanks
Pete
Just a quick experiment which I had chance to try that I thought may be worth sharing.
A question that I have pondered and im sure many others have is "Should I sell my current GPU and upgrade to a new one, or buy a second card to Crossfire/SLI instead?"
This question was a little academic for me as my ITX board only supported a single card, which led me to upgrade to a new GTX 970 from my older HD7950.
However, I am currently building another PC for a friend and the opportunity came up to try and answer this question using 2x HD7950s vs the GTX 970.
So with out further ado here are the specs of the hardware I used and results of some bench tests:
Motherboard - Gigabyte Z77X-D3H
CPU - Intel I5 3570K @ stock clocks (with 3.8ghz turbo)
CM Hyper 212 CPU Cooler
8GB Ram (1333ghz)
40GB HDD
Enermax Platimax 500W PSU
Corsair CX500W PSU (had to use 2 x PSUs for crossfire setup)
(All the benchmark programmes I used are the free download versions so are all the basic bench tests)
The first Benchmark I tested with was Unigene Heaven, I also used a single HD7950 for comparison to see what the gain may be when crossfiring.

As you can see adding a second HD7950 almost doubled the result, and gave an improvement over the single GTX 970
Next was 3DMark 11

The crossfire setup stretched ahead again but only marginally compared to the GTX970, though this was for the overall P score.
Looking just at the graphics score, the gap over the 970 increased again, and once more almost doubled that of the single card

Finally I tried the test using the Catzilla Bench test

Here you see the GTX 970 leaps far ahead of the HD7950, with the Crossfire set-up actually scoring less than the single card.
This benchmark was obviously not compatible with my crossfire set-up, which is always the Achillies heel of dual graphics cards, not always being supported in all benchmarks and of course games.
So did I answer my question?
Yes, for me at least.
The GTX 970 came in at around £50 more than it would have cost me to keep my old card and to buy a second HD7950.
I do not play a large variety of games, and although I did not get to try the set-up on the games I play, I do know that crossfire is compatible and likely to give a better performance than the GTX970.
Having said that, to upgrade to a crossfire set-up I would have had to have changed my motherboard, case and upgraded my PSU, in addition my electricity bill would also have taken a not so insignificant hit, so for me the choice I originally made was the right one, the GTX970.
Obviously the answer to this question may be different to someone else who already has a compatible motherboard and PSU, but I would advise to search the web to see if the games you play are compatible, and of course remember future games may not be, or least may take some time until they are Crossfire/SLI ready. Another note worth a mention is future Direct X and Mantle compatability for older gen cards may also eventually become an issue.
It is however tempting to try, and you can get mega gains for not such a massive outlay on the right games/bench tests.
I hope you found this little test of some interest and maybe even of a little help.
But at the end of the day, the choice as "Our Graham" used to say, is yours.
Thanks
Pete