With the Sapphire ATI Radeon HD 4850 Toxic Edition, Sapphire delivers an enhanced ATI 4850 graphics card with a boosted clock speed and effective Zalman cooler.

We got a chance to ttest Sapphire's Radeon HD 4870 card a few weeks ago and we were pretty impressed. Both its performance and graphics quality levels were incredibly competitive for the price and the 4870 was a clear winner. Our admiration for ATI's latest graphics chipset has only grown since then as it leads the pricier nVidia GeForce GTX 260.

This month, we've turned our attention to the 4850 card – a still cheaper version of the ATI 4800 range. Indeed, Sapphire's HD 4850 is such good value it is able to squeeze itself into the £150-and-below graphics card chart.

Nor is this an ordinary rendition of the 4850 chip. Sapphire routinely offers special Toxic Editions of its best cards that ramp up the clock speeds or memory, or come with an enhanced cooling system. With the Sapphire ATI Radeon HD 4850 Toxic Edition, Sapphire delivers in two of those three areas.

The Sapphire ATI Radeon HD 4850 Toxic Edition's memory is a standard 512MB of GDDR3 - a major difference between the 4870 and the 4850 is that the latter comes without the 4870's GDDR5 RAM. However, the memory clock speed is ratcheted up from 993MHz (1,986MHz DDR effective) to 1.1GHz (2.2GHz DDR effective).

Similarly, there's a standard 256bit memory interface, but the Sapphire ATI Radeon HD 4850 Toxic Edition's basic memory bandwidth of 63.6GBps is raised to a more palatable 70.4GBps. The core clock speed has also been upped from 625MHz to 675MHz.

For many users, the most interesting aspect of the Sapphire ATI Radeon HD 4850 Toxic Edition will be the Zalman cooler. It's considerably more effective than those typically found on graphics cards and we found the Toxic extremely quiet and efficient.

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With the Sapphire ATI Radeon HD 4850 Toxic Edition, Sapphire delivers an enhanced ATI 4850 graphics card with a boosted clock speed and effective Zalman cooler.

The Sapphire ATI Radeon HD 4850 Toxic Edition, then, is an extremely powerful version of the 4850 chipset and is easily the fastest of the graphics cards in our sub-£150 chart. It may not reign supreme for long, however, as the nVidia GeForce 9800 GTX chip is soon to get a price cut: this is likely to bring it within striking distance of the Toxic.

Here it gets quite interesting, as the enhanced Sapphire ATI Radeon HD 4850 Toxic Edition was neck and neck with the GTX in Crysis at mid-range resolutions and marginally beat it in World of Conflict, Stalker and Fear.

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Sapphire ATI Radeon HD 4850 Toxic Edition: Specs

  • ATI Radeon HD 4850
  • 512MB GDDR3
  • 625MHz Core Clock
  • 993MHz Memory Clock (1,986MHz DDR effective)
  • 400MHz Ramdacs
  • 800 Stream Processors
  • PCI-E Interface
  • TV Out/Video In yes/no
  • DirectX 10.1
  • DVI
  • 2-year warranty
  • ATI Radeon HD 4850
  • 512MB GDDR3
  • 625MHz Core Clock
  • 993MHz Memory Clock (1,986MHz DDR effective)
  • 400MHz Ramdacs
  • 800 Stream Processors
  • PCI-E Interface
  • TV Out/Video In yes/no
  • DirectX 10.1
  • DVI
  • 2-year warranty

OUR VERDICT

The Sapphire ATI Radeon HD 4850 Toxic Edition is a great value card that is significantly enhanced by the addition of the Toxic elements. The tweaks are enough to turn the Sapphire HD 4850 from a chip that's ever so slightly slower than the 9800 GTX to one that's faster overall. This graphics card is a real stunner and, if you've a budget of £150 and no more, we believe the Sapphire is a fantastic deal.

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