7:03 pm | May 13, 2012

Author: admin | Category: Computers | Tags: CUDA, GPU, GTX, SMX | Comments: None

Introduction and architecture

The Nvidia GeForce GTX 690 has been hailed by the green graphics giant as ‘the best graphics card that’s ever been made.’

That’s quite a claim, but bandying around phrases like ‘trivalent chromium plating’ and ‘injection moulded magnesium alloy’ in relation to its design means this expensive ol’ graphics card bears serious inspection.

So yeah, before we get into all the tech pornography that is the Nvidia GTX 690 reference design – here showcased by EVGA – and it’s technological make up, we do need to talk about that £830/$1000 price tag.

That’s a huge amount of money to spend on any PC component, and granted, 90% of us would never even think of dropping that much money on a graphics card. But there are people out there with a penchant for the fastest whatever available and with the means to purchase them.

We’ve already covered the £1,400 Intel Xeon E5-2687W, the absolute pinnacle of CPU performance, and in relation the GTX 690 is actually rather cheap…

Okay, ‘cheap’ might be pushing it a little but you can see where we’re going with this.

As the top fantasy graphics config we’ve been recommending the Nvidia GTX 680 in SLI configuration up to now, and that setup will cost you the same sort of price as a single GTX 690.

While that pairing is still faster there are significant advantages to just opting for a single graphics card – even one sporting two powerful GPUs – over the SLI configuration.

There’s also the fact system integrators will be looking at the Nvidia GeForce GTX 690 with interest.

It will make things are lot easier in fashioning serious dream machines compared to setting up an SLI rig with hardcore cooling.

There has been consternation though about the GTX 680 not necessarily being the top-end Kepler GPU – more like the sort of architecture we were expecting lower down the Kepler tree – and yet still being priced at the top end.

While, as the fastest graphics card around, Nvidia has the right to price it in relation to the AMD competition, others have claimed it still has a responsibility to try and drive hardware adoption in the PC gaming sphere. Pricing the Kepler cards so high means that they are beyond the reach of most gamers.

Whatever the ethics, or the pricing structure of the graphics card market, there is still no getting away from the fact the Nvidia GeForce GTX 690 is one sexy bit of silicon wondrousness.

Architecture

So what is it that makes the Nvidia GeForce GTX 690 ‘the highest quality, most striking video card ever built?’ Well, that’s what Nvidia reckons, so what’s it actually talking about?

Architecturally it’s talking about a hybrid of the GK104 GPU, which powers both the GTX 680 and the Nvidia GTX 670, with two of those graphics chips crammed onto the same single slice of printed circuit board.

Why a hybrid?

Well, each of the GPUs in this EVGA GeForce GTX 690 contains the same number of CUDA cores that are in the GK104 in the GTX 680. That means we’re looking at a total of 3,072 of those cores in the twin GPUs.

The two GK104 GPUs aren’t running at GTX 680 speeds though, they are running at 915MHz instead; the same base clock as the new GTX 670 spin of the chip.

We’re also looking at a huge 4GB of GDDR5 (two banks of 2GB) graphics memory sat around the two GPUs. That’s running at the same 6Gbps speed as the memory on the GTX 680.

In order to keep these two chips chock full of juice there’s a 10-phase power setup in between the two chips, with twin 8-pin PCIe power connectors taking the load from the PSU.

That gives the EVGA GTX 690 a relatively conservative 300w TDP. When you think both the previous generation dual-GPU cards – the Nvidia GTX 590 and the AMD Radeon HD 6990 – came with vast power requirements, hitting 365W and 375W respectively, that’s rather efficient.

But the Nvidia GeForce GTX 690 isn’t all about the internal architecture; the actual build of the card screams quality – and expense – from first glance.

The chassis of the card is built from riveted cast aluminium with that trivalent chromium plating. The chrome finish is then highly durable, but is more about aesthetics than anything else.

After all if your graphics card casing needs to be that durable you really need to question what you use it for.

The central fan housing is built from injection moulded magnesium alloy and if that sounds familiar you’re probably a petrol-head as it’s used in the construction of the beautiful Bugatti Veyron’s engine.

Each of the GPUs in turn have their own separate cooling unit, using vapour chamber technology, around a centralised fan. Beneath that fan is a grooved plate to help direct airflow beneath the heat sinks and fins.

The result then is a well-cooled card, that still manages to remain relatively quiet during operation.

Benchmarks

The impressive thing at first glance is just how close the performance of the GTX 690 and GTX 680 SLI is. Despite having a much lower base clock the GPU boost tech manages to get the twin GPUs up around the same sort of performance.

The next thing to note then is just how close a pair of GTX 670s gets to that performance.

At this level the sort of performance drop you’re getting between the two options would be very difficult to see in-game.

DirectX 11 tessellation performance

DirectX 11 gaming performance

DirectX 10 gaming performance

Performance

Nvidia has done a great job engineering the GeForce GTX 690.

Squeezing two graphics cards into one is something it is now used to doing of course, but the fact it has managed it without sacrificing too much straight line speed is impressive.

The twin pairing of two GTX 680s in SLI is still the top performance configuration, if you’ve got the ready cash, the airflow through your chassis and one mother of a power supply. But the Nvidia GeForce GTX 690 is incredibly close in terms of raw frame rates to that setup.

You’re losing out on one or two frames per second on average at most in opting for the single card versus the SLI setup.

That just demonstrates how well the GPU boost technology pushes on from that initially low 915MHz base clock.

It’s also possible to push the performance even further should you want to really stress that £830/$1,000 purchase of yours. We managed another, stable, 110MHz offset, which translated to gaming performance of around 1,155MHz.

Still, that overclock only gave us another couple of frames per second across the board, but that’s enough to push it ahead of the GTX 680 SLI configuration.

The problem for the Nvidia GeForce GTX 690 though comes in the shape of the recently released Nvidia GeForce GTX 670 cards.

Obviously on their own they represent no real challenge to the majesty of the GTX 690, but jam a pair of them into a system and for nigh-on £200/$200 less you’ve got a setup that performs almost as well.

As the GTX 690 is only just short of the GTX 680 in SLI, so is the GTX 670 SLI setup.

A pair of Nvidia GTX 670s though still needs a hefty PSU with the requisite PCIe power connectors to make good of the configuration.

Under full load the Nvidia GeForce GTX 690 draws a not-inconsiderable 416w, but that is still a lot less thirsty than either SLI configurations of the GTX 670 or GTX 680, at 430W and 480W respectively.

Verdict

So yes, the Nvidia GeForce GTX 690 is a vastly expensive card, and is also incredibly niche. But then so is every SLI graphics configuration out there.

If you’re talking about the absolute fastest fantasy graphics setup then we’d have previously been talking about a pair of GTX 680s in SLI. What the GTX 690 does then is throw that into question.

Of course the absolute fastest is still the GTX 680s, but only by a hair’s breadth. There are many more reasons to opt for the slightly slower GTX 690 instead.

The primary reason is one of power demands.

In both fully loaded and idle states the GTX 690 draws less power than either Nvidia GTX 670 or GTX 680 SLI configurations. It also only requires a pair of PCIe power connectors making it more universally compatible with your PSU.

That said, if you’re spending this much on your graphics, chances are you’re building your entire rig around it.

And in the rig-building world is where the GTX 690 is probably most likely to be seen.

System integrators are going to be able to craft impressively powerful machines from this card without needing elaborate power supplies or vast chassis to house it.

But for that to happen supply will need to be there, and there is a part of us that struggles to believe we’ll see that many Nvidia GeForce GTX 690s out in the wild.

Where we also struggle with the GTX 690 is in the choice of cooling solution Nvidia has employed. We understand that having the fan sat in between the two GPUs allows them both to be cooled equally, but it also means half the hot air is being exhausted inside your PC.

In many PC configurations that would automatically mean a constant blast of hot air pushing over your storage drives. Obviously then component layout is going to be vital to any GTX 690 build, and you’ll probably need an exhaust fan pulling out of the chassis on the front.

We can also understand, now that the GTX 670 has been released, why Nvidia decided to push the GTX 690 out of the door only a week ahead of its little brother.

A pair of those cheaper cards will offer very similar performance metrics compared with the very pricey GTX 690.

You’ve got to really care about the extra 14W of fully loaded power draw to want to spend an extra £200/$200 on the more expensive card.

We can’t help but feel the trivalent chromium plating and injection moulded magnesium alloy are only there in a bid to justify the vast expense of the card.

Yes, the Nvidia GeForce GTX 690 is a very elegant solution to the SLI problem, with its luxury components and design elements, but that price tag still sticks in the craw.

Even more so with far cheaper options offering very close performance.

We liked

The design of the Nvidia GeForce GTX 690 is immaculate. From the fan-housing to the chromed aluminium chassis it’s a thing of technological beauty.

It’s also impressive that Nvidia has managed to get so close to the full GTX 680 SLI performance in this single slab of PCB.

The comparatively low power draw and quiet operation of the card also impresses us.

We disliked

The big issue we have with the GTX 690 is the appearance of the GTX 670 just a week after launch. A pair of those far cheaper cards will give you incredibly close performance compared with the more expensive card.

And that price tag is another thing that is tough to love about the GTX 690. It’s true that it is no more than a pair of GTX 680s, but does it really cost as much to manufacture one of these as two GTX 680s?

We’re also a little displeased at the amount of hot air that will inevitably be left washing around inside your PC as the GTX 690’s cooling setup blasts half of the heat back into the chassis.

Verdict

The GTX 690 is a beautifully designed, and wonderfully engineered graphics card. Truly a thing of tech pornography.

That said the performance it has on offer isn’t anything wondrous compared to the cheaper GTX 670 SLI alternative.