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Plugging the Performance Gap

Plugging the Performance Gap

Since the release of their impressive Radeon HD 4870 and HD 4850, ATI have wasted no time in flooding the market with a flurry of new products. Since June, apart from the HD 4870 and HD 4850, we have also seen the launch of the HD 4870 X2, HD 4670, HD 4650, HD 4550, and HD 4350.

Each of ATI's new Radeon cards offers competitive price and performance that matches that of its arch-nemesis, NVIDIA. However, despite having no less than seven cards in their line-up, there still remains an area in the performance band that has yet to be addressed - a significant performance gap between the HD 4850 and HD 4670. We spoke about this in our review of the HD 4670, and also mentioned that ATI still has a card to play. This card has finally been played today and it is none other than the Radeon HD 4830, which we shall be taking a look at in the form of three such cards from HIS, PowerColor and Sapphire.

Before we embark on our benchmarking however, let us introduce this new Radeon HD 4830 GPU, codenamed RV770LE. First and foremost, if you guessed that it is a close derivative of the HD 4850 and HD 4870, you're right on the mark. In fact, it is really a stripped down HD 4850 with fewer stream processors and lower core and memory clock speeds.

If you remember the HD 4850, that has 800 stream processors and core and memory clock speeds of 625MHz and 1986MHz DDR respectively. The Radeon HD 4830, on the other hand, has 640 stream processors and core clock speed of 575MHz and memory clock speed of 1800MHz DDR. And as far as we know, everything else remains intact and similar, with ATI positioning this as the GPU to help fill up the gap between the HD 4850 and HD 4670.

What about pricing? We are glad you asked. When quizzed, ATI was rather coy about pricing and will only say that the HD 4830 will be priced below US$150 (S$223), which makes it about US$30 - US$40 cheaper than the HD 4850 (prices from Newegg), and at that price, it is nearly double that of the Radeon HD 4670. Its direct competitor, the GeForce 9800 GT is going for about US$120 - US$130, so in this price sensitive segment, how low the HD 4830 will go below US$150 is probably what will make or break it.

Moving on, let's now take a closer look at the technical specifications of the Radeon HD 4830 and its competitors.

The ATI Radeon HD 4830 and competitive comparison SKUs
Model ATI Radeon HD 4830 512MB ATI Radeon HD 4850 512MB ATI Radeon HD 4670 512MB NVIDIA GeForce 9800 GT 512 MB NVIDIA GeForce 9600 GSO 384MB
Core Code RV770LE RV770 RV730 G92 G92
Transistor Count 956 million 956 million 514 million 754 million 754 million
Manufacturing Process 55nm 55nm 55nm 65 / 55 nm 65nm
Core Clock 575MHz 625MHz 750MHz 600MHz 550MHz
Stream Processors 128 Processors (640 Stream processing units) 160 Processors (800 Stream processing units) 64 Processors (320 Stream processing units) 112 Stream Processors 96 Stream Processors
Stream Processor Clock 575MHz 625MHz 750MHz 1500MHz 1375MHz
Texture Mapping Units (TMU) or Texture Filtering (TF) units 32 40 32 56 48
Raster Operator units (ROP) 12 16 8 16 12
Memory Clock 1800MHz GDDR3 2000MHz GDDR3 2000MHz GDDR3/DDR3 1800MHz GDDR3 1600MHz GDDR3
DDR Memory Bus Width 256-bit 256-bit 128-bit 256-bit 192-bit
Memory Bandwidth 57.6GB/s 64GB/s 32.0GB/s 57.6GB/s 38.4GB/s
PCI Express Interface PCIe ver 2.0 x16 PCIe ver 2.0 x16 PCIe ver 2.0 x16 PCIe ver 2.0 x16 PCIe ver 2.0 x16
Molex Power Connectors 1 x 6-pin 1 x 6-pin No 1�x 6-pin 1�x 6-pin
Multi GPU Technology CrossFireX CrossFireX CrossFireX SLI SLI
DVI Output Support 2 x Dual-Link 2 x Dual-Link 2 x Dual-Link 2 x Dual-Link 2 x Dual-Link
HDCP Output Support Yes Yes Yes Yes Yes
Street Price < US$150 ~US$179 ~US$79 ~US$140 ~US$100