So you have some money to spend on a nice graphics card, and you're wondering if you should go for an SLI setup with two mid-range cards, or buy a single high-end card.
In this case, I'll be subjectively
comparing 2x ASUS GTX660 DirectCU II in SLI vs 1x Galaxy GTX680GC.http://www.ncix.com/products/?sku=76367
- ASUS GTX660 OC DirectCU II - $220 x2 = $440CAD.http://www.ncix.com/products/?sku=70704
- Galaxy GTX680GC - $567CAD (this model is no longer available. The GTX680GC 4GB is available for $572.55, and the GTX680GC white edition is available for $549.99, but has a different cooler (triple fan vs double fan).
So, it's a valid question. Should somebody who's looking at building or upgrading a mid-high range gaming rig look for 2x smaller cards, or 1x higher end card. There are advantages and disadvantages to both. I have experienced both solutions, and will give my subjective opinion
. You can go look at reviews and FPS averages yourself, they're all over the web. This is going to deal more with user experience.PRICE:
Clearly, 2x GTX660's (custom cooled) are cheaper than 1x GTX680 (custom cooled). By going with the GTX660's, you'll be saving about $120 vs buying the GTX680. Advantage: 2x GTX 660'sPERFORMANCE
If you look at benchmarks, you'll see that the GTX660's in SLI pull slightly ahead of the GTX680. We're not talking much, but about 10-15 frames per second. This is in games that scale SLI well. I play BF3, and I play it on ultra with all the eye candy turned on, at 1920x1200. BF3 scales very well on SLI. I am indeed seeing about 10FPS more with the GTX660's than with the GTX680. This is simply by turning on render.fpsdraw in BF3, and observing the FPS number in the top right hand corner. It is by no means a scientific comparison, but I can confirm that in BF3 at least, the GTX660's do not perform any less than a GTX680. YMMV. Different games scale differently. You may see less performance than a GTX680 in certain games. Advantage: DrawCOMPATIBILITY
It is often said that one single large card is better than two smaller cards. Newer games do not always have SLI profiles ready until a couple of weeks after release. Even then, these games may be buggy for a little while until driver issues get resolved (if ever). If you like to play a lot of new releases immediately upon launch, SLI may not be for you. If, however, you're like me, and you play a game for a long time after release, without trying a lot of new titles, then this may not be an issue. For BF3, I have experienced zero compatibility issues. Advantage: GTX680 MICROSTUTTERING
Newer methods of benchmarking (using frame times vs FPS, and using video capture cards vs FRAPS) are revealing microstuttering (drastically uneven frame times resulting in 'unsmoothness' during gameplay) in a lot of video solutions. The very nature of SLI promotes microstuttering to some degree. Frames are alternatively rendered by each card (the master card and the slave card). Frames rendered by the slave card are sent to the master card, then sent to the display (plugged into the master card). This additional pathway vs a single GPU increases frame latency, potentially resulting in microstuttering. The degree and severity of microstuttering is usually determined by the effectiveness of the graphics drivers. Personally, I have not noticed much microstuttering at all. During most game play (BF3), the illusion of motion appears to be smooth and fluid. There is however, the occasional 'hitch' from time to time. It doesn't happen oftern, (every five minutes or so, if at all), but it is definitely there, whereas with the GTX680 it never happened. Is it enough to affect my gameplay experience? No. Each person is different, however. Somebody else may be able to perceive Microstuttering where I see smooth gameplay. For me, however, Microstuttering is so far not an issue. Advantage: Draw, but leaning towards the GTX680QUIETNESS
First let me say that I was blown away by how quiet the GTX660's in SLI are. I by no means have a silent rig. My Coolermaster 690II Advanced is populated by a few Corsair AF fans (both 120 and 140mm), all throttled by the included resistor (to run at slower RPM's), and the H80i in Push/Pull is by no means the quietest AIO in existence. BUT, it is not a LOUD case. It certainly does not sound like a jet plane. More like a constant whisper.
The GTX680GC couldn't be heard over the rest of the rig at idle, but put some load to it, and the fans would ramp up to 40%, and you could definitely hear it over the rest of the rig. It was not what I would call 'loud', but it definitely made a distinguishable noise. Manually increase the fan RPM's to >70%, and the card made a significant 'whooshing' noise.
The GTX660's in SLI, however, cannot be heard at all, even under load. For whatever reason (lower power chip, better heatsink, whatever) the fans don't increase past 20% while under normal game load. These cards are SILENT, and can't be heard over the rest of my rig. Start adjusting the fans manually, and it takes a fan RPM of 60% to even begin to hear these two cards. Set the fans to 100%, and they were no louder than the GTX680 under normal loading (40% fan speed).Advantage: 2x GTX660's - by a landslideRELIABILITY
Cards fail. They don't all fail, but I've had a few cards in need of an RMA in my lifetime. First, let me say that Galaxy has excellent customer service. I had a to RMA my 680 with them, and they were very accommodating and easy to deal with. That being said, if you ever have to RMA a single card solution, your gaming experience will stop until you have your new card in your rig. With an SLI solution, if one card fails, you still have another one to fall back on. Reduce your game settings accordingly to run on one mid-range card, and keep on playing for the month that it takes to RMA your other card. This is a HUGE plus. Advantage: 2x GTX660'sCONCLUSION
So, what should you buy? 2 smaller cards in SLI, or one larger single card? Well, that depends. If you like to play a lot of brand new titles, or can perceive microstuttering, then definitely go for the single larger card (like a GTX670 or a GTX680). If, however, you're like me, and you continue playing titles for a long time after release, and can't perceive any microstuttering, then you may very well be better off with two smaller cards in SLI. You stand a good chance of saving money, have a potentially quieter rig (although it all depends on the cooling solution for your specific cards) and you have redundancy in case of failure.
I know that I'm happier with my 2xGTX660's than my single GTX680. YMMV.
My Rig: Z77A-G45; 3770K; Coolermaster Gemin II; 2x4GB Kingston HyperX 1600Mhz; MSI GTX960; 2x 128GB Crucial M4 SSD; 4TB WD Red; 2x 2TB WD Green; PC&C 750W PS; Corsair Carbide 600C;