ATI Radeon HD 4670

Verdict: Two sub-£70 graphics cards that can both run Crysis.

Often the phrase 'budget graphics card' is enough to have hardware enthusiasts scoffing at the poor fool who deemed the subject worthy of mention. Times are changing, though, and many people simply don't have £400 to throw at shiny new high-performance graphics cards at the moment.

What's more, the rise of the console as a lucrative market for game developers has made cross-platform development the way to go, with the effect that many new games run well on fairly modest PC hardware. With the combination of these two mostly financial factors, you may be surprised at how much gaming performance you can secure for less than £70 with the newly released Radeon HD 4670 and Nvidia GeForce 9600 GSO.

Specifications

Although the GeForce card on review is a pre-overclocked XFX GeForce 9600 GSO XXX, it costs only £6 more than the stock-speed Sapphire Radeon HD 4670. At first glance, it looks as if the Sapphire has the edge over its price-comparable competitor. It's a stock-clock card, but even so the GPU runs at 750MHz - 70MHz more than the core of the pre-overclocked XFX, which runs at 680MHz. The core of a standard GeForce 9600 GSO runs at just 550MHz.

The Sapphire also has more than three times the number of stream processors: 320 compared to the 96 of the XFX. However, the Nvidia's stream processors are more complex and can potentially carry out more work per clock than the ATI's stream processors. The Nvidia stream processors also run faster than those of the Sapphire ATI card, which operate at the same 750MHz frequency as the rest of the GPU. The stream processors of a GeForce 9600 GSO usually run at 1.375GHz but XFX has overclocked them to run at 1.7GHz.

The Sapphire has the faster memory - 1GHz (2GHz effective) rather than the 950MHz (1.9GHz effective) of the XFX. The usual speed of the memory on a GeForce 9600 GSO card is 800MHz (1.6GHz effective), so again this is a big overclock from XFX. Both cards feature GDDR3 memory, although the Sapphire has 512MB compared to the XFX's 384MB.

Perhaps a more important factor is the difference in the width of the cards' memory interfaces. The GeForce uses a 192-bit-wide memory interface, while the GPU and memory of the Radeon card communicate over an interface 128 bits wide. These interfaces equate to memory bandwidths of 32GB/sec for the Sapphire and 38.4GB/sec for the XFX, giving the XFX card the edge over the Sapphire. Overall, though, the specifications of the two cards are reasonably close.

Both cards feature two DVI connectors, and while both support HDCP over DVI, the Sapphire also has a DVI-to-HDMI converter in the box. In response, the XFX has a copy of Company of Heroes, just in case you haven't had the chance to play it yet. While the GeForce requires a 6-pin PCI-E power connector from your PSU, the Radeon draws all its power directly from the PCI-E slot.

Performance

We were surprised at the levels of performance we obtained from such inexpensive cards but, with the specs so close, we were curious to find out which would be the last card standing after testing. The first game we tried was Call of Duty 4, and at 1,680 x 1,050 both cards managed a playable minimum frame rate. The XFX was the faster of the two, however, with a 30fps minimum compared to the Sapphire's 25fps minimum.

In Race Driver: GRID, both the Sapphire and the XFX coped well at 1,680 x 1,050 with 2x AA. Again, the XFX was the faster card, as the game never dipped below 45fps, while the Sapphire produced a minimum frame rate of 39fps. However, the Sapphire proved to be faster at 1,920 x 1,200 with 4x AA, achieving a minimum of 31fps compared to the XFX's 23fps minimum.

We didn't expect Crysis to run well on either card, even at 1,024 x 768, but the XFX surprised us with a smooth and enjoyable minimum of 33fps. The Sapphire didn't fare badly either, with a 25fps minimum.

Although we managed to get the Folding@home client to start on the Sapphire, it crashed after a few seconds, so we were unable to obtain a score for the card. Clearly, the BETA Catalyst driver needs some work in this department. The XFX produced an impressive 4,557ppd from a project p5014, however.

Overclocking

Only PowerStrip was able to recognise the Sapphire at the time of writing, as the HD 4670 GPU is so new. However, increasing the clocks actually made the frame rate drop. We expect a Catalyst update to address this (although 8.9 still doesn't recognise the card), as well as the instability with the Folding@home client. Frustrated, we turned to the XFX and tried PowerStrip with greater success.

XFX has overclocked the card a lot already, but we managed to coax a little more speed out of it. We boosted the core from 680MHz to 720MHz and the memory from 950MHz to 1.05GHz (2.1GHz effective). At these speeds, the XFX was still unable to play Crysis at 1,280 x 1,024, even though the minimum frame rate was boosted from 13fps to 19fps.

Conclusion

As graphics card technology advances and the financial benefits of developing games for consoles and PCs concurrently take effect, the world of budget graphics cards is proving to be worthy of attention. That both cards can play Crysis at 1,024 x 768 - a task that £200-plus cards struggled to do only six months ago - was a surprise. Less demanding games such as Call of Duty 4 and Race Driver: GRID are eminently playable on both cards at 1,680 x 1,050, and occasionally even higher settings.

In this battle between the Radeon HD 4670 and XFX's massively overclocked GeForce 9600 GSO XXX, the latter card emerges the victor. In almost all of our test games and at every resolution, the XFX was noticeably faster. And as the cards are similarly priced, the choice is clear. The Sapphire is faster in only a few situations (GRID at 1,920 x 1,200, for example) but we suspect that anyone buying a sub-£70 graphics card won't have a 24in TFT with which to use it. It's a shame we couldn't overclock the Sapphire but, for the sake of £5 more, the XFX's extra performance and overclockability makes it the winner.