The fear that used to be attached to running an SLI setup has largely vanished over the last year or so.
Thanks to maturing driver sets and great mid-range cards there really has never been a better time to drop in that second card. And with the incredi-card, the GTX 460, there has rarely been a better SLI card either.
So thankfully the thrill that was also attached to the idea of running a bleeding-edge SLI system hasn't gone, but now it's a far more practical solution. In fact you may find us telling you that in many cases two really is better than one.
Previously we'd have always said that for the best day-to-day performance for your money you should always go for the fastest single-GPU card your money would allow. Now it's not so black and white as even the high-end cards are struggling to compete with a pair of mid-range wonders like the GTX 460.
The GTX 460 arrived last month and wowed us with its double-ended loving of both fantastic value and great 3D performance. The only slight fly in the ointment was the fact that it arrived in two very different spins from the outset.
We had both the full-fat 1GB versions as well as the cut-down 768MB cards. With barely £20 separating the two it was a no-brainer at that level which card to go for – the 1GB card, especially at the higher-end of the desktop resolution scale, was a clear winner. The limited memory size and bus, combined with a fair few less ROPs, meant the 768MB card suffered by comparison to its smarter sibling.
Both versions of the card though carry the same redesigned Fermi GPU from Nvidia. The GF104 chip is a far more streamlined version of the original Fermi chip that powers the £400 GTX 480. Nvidia has managed to cram more of the good stuff into less streaming multiprocessors making for a high-performing card that costs far less to produce.
Poor GTX 480…
The GF104 chip also has something else up its sleeve. Well actually it's more like under its hat; you see there is so much headroom in there for this chip that you can seriously overclock even the stock cards with the basic Nvidia reference cooler.
An overclocked 1GB card will then hit the same sort of speeds as a GTX 470, with an overclocked 768MB card not too far behind it. So what can they do when you get a pair of twins on the case?
The simple answer is astonish. That's what these cards can do, because now there is simply no reason to go out and pick up the top end cards if you've got a mammoth display because a pair of either version of the GTX 460 will do better. That's right, you're spending less and getting more. The diminishing returns that have dogged the SLI dream for years is a thing of the past.
The simple comparison is Nvidia's top-of-the-line card, and the first of the Fermi lineup to arrive, the GTX 480. At the time of launch we got all hot under the collar about it. Not just because it was blisteringly fast for a single-GPU card, but because it was so blisteringly hot in itself that it rendered all the air-conditioning in the building irrelevant.
That card has since dropped in price to a vaguely reasonable £390-odd. Interesting as if you picked up a pair of these EVGA Superclocked GTX 460 768MB cards that would set you back…that's right…£390-odd. It's even more interesting in light of the bargainous nature of Inno3D's reference 1GB cards that can be had for as little as £360 for the pair.
Both sets of GTX 460s, irrespective of memory constraints, absolutely hose their GTX 480 daddy in practically all metrics, most especially at the high-end 2560x1600 resolution.
As for AMD's top card de jour, the £500 multi-GPU HD 5970, it actually stands up better than the GTX 480. But then for the cash you'd hope so. Unfortunately for AMD though it doesn't fare /much/ better. The Just Cause 2 benchmark is the only place the Texans can hold their head up high, in DiRT2 and Far Cry 2 it lags behind noticeably.
Double the fun
Interestingly a pair of overclocked 768MB cards actually beats a pair of the stock-clocked 1GB GTX 460s at the 22-inch res of 1680x1050. It's only by a little way, and notably not in the tessellation-heavy Heaven benchmark, but it means that potentially you could hit these speeds for only £300.
How? Well, EVGA's Superclocked cards are still only reference cards, admittedly they are hand-picked, and factory overclocked, but they are still just the basic GTX 460. You can pick up a Palit GTX 460 768MB for only £150, and that comes with its own cooler too.
Theoretically then overclocking two of these babies, even up past what the Superclocked cards are sitting at, will give you the sort of performance people with GTX 480s warming up their PCs would cry for.
We are aware though that realistically few of us can actually be bothered going through the inevitably slow process of safe overclocking, or are willing to take the risk with their just-unwrapped hardware. If you do still wanna hit the same performance heights then a stock-clocked 1GB will do just as well for £350-odd.
Essentially what this all means is that if you're looking for something to power that 30-inch panel you've always wanted to have running in its native resolution a pair of GTX 460s is the way to go. Forget both of Nvidia and AMD's top cards, this will get your more performance and for less cash.
The only choice is then which do you go for? If you're up for a bit of easy overclocking on a budget picking up a pair of £150 GTX 460 768MB cards will suit you down to the ground. If you don't want to take the risk then a pair of 1GB cards will give you almost the same overclocked performance for only £50 more.
The Superclocked cards though still have a hard time justifying themselves. Sure they give impressive performance and for the same price as a GTX 480, but the cheaper stock 768MB and 1GB versions will keep you just as happy in your SLI gaming.
