Palit Revolution 700 Deluxe Radeon HD 4870 X2 Review :: Palit Revolution 700 Deluxe Radeon HD 4870 X2 Features

12-05-2008 · Category: Hardware - Video Cards

By Ben Sun
  • HD 4870 X2
  • Bus interface: PCI Express® 2.0
  • Memory Support: 2048MB GDDR5
  • Memory Interface: 512 bit
  • Memory Clock: 3800MHz (950 x 4)
  • Core Clock: 750 MHz
  • RAMDACs: 400 MHz
  • Full Microsoft® DirectX® 10.1 Shader Model 4.1 support
  • Dual-link DVI output supports 2560x1600 resolution display
  • Dynamic geometry acceleration
  • Game physics processing capability
  • ATI PowerPlay™ technology
  • ATI CrossFireX™ Multi-GPU Technology
  • ATI Avivo™ HD video and display technology
  • HDCP capable
  • 4-in-one display support includes CRT, HDMI, Dual-link DVI, and DisplayPort
  • Built for Microsoft® Windows Vista™
  • DisplayPort
  • Certified for Windows Vista
  • Dual PWM Cooling fan with four heatpipe cooling solution
  • 3-Slot cooling solution
  • 4-in-1 display outputs

Brand Name Palit
Part Number Revolution 700 Radeon HD 4870 X2
Graphics Chip RV770XT
Core clock 750
Shader Clock 750
SPs 800 x2
Process 55 nanometer
Transistors 956 million x2
Memory clock 3.8GHz effective
Memory Interface 256-bit
Memory bandwidth 243.2GB/second
Memory Size 2048
ROPs 32
Texture Filtering Units 64
Texture Filtering Rate 40.6GB/second
HDCP Support Yes
HDMI Support Yes (via adapter)
Connectors Dual Link DVI, DisplayPort, HDMI, VGA
RAMDACs 400MHz
Bus PCI Express 2.0
Form Factor Triple slot
Power Connectors 1x6-pin, 1x8-pin

The HD 4870 X2 uses two RV770XT chips that were found on the HD 4870 card. Each chip has 956million transistors and is on TSMC's 55 nanometer process. That means that the HD 4870 X2 has 1.912 Billion transistors or more than the single chip NVIDIA GTX 280 has. The core has 800 Stream Processors set up to do 160 5D operations in a single cycle. The 4870 X2 has 1600 Stream Processors capable of 1.2 GigaFLOPs computing power each chip or 2.4 GigaFLOPS total.

The Revolution 700 Deluxe Radeon HD 4870 X2 has 2048MB of GDDR5 memory clocked at 950MHz, a 50MHz increase over the reference HD 4870 X2 clock speeds. GDDR5 memory allows memory bandwidth to be doubled over the same clock speed GDDR3 memory. The HD 4870 X2 has two 256-bit memory buses, one for each RV770XT chip. This means the total memory bandwidth on the card is a whopping 243.2GB/second.

The regular clock speed of the Palit Revolution 700 Radeon HD 4870 X2 card is 750MHz, or the same as ATI's reference clock. Palit decided to clock the card at the reference clock, as the HD 4870 X2 is not likely to be fillrate or texture limited with two graphics chips. The HD 4870 X2 can run in PowerPlay mode which conserves energy when 2D operation is detected instead of running the card at full steam all of the time like most video cards on the market do.

ATI introduced support for DirectX 10.1 with the launch of the HD 3870 last year. DirectX 10.1 has some additional features like improved anti-aliasing algorithms and improvements to Global Illumination on the graphics side of things. NVIDIA says of course that DirectX 10.1 is not a necessary feature but it is better to be compliant, as future hardware will need to support DirectX 10.1 in order to support DirectX 11. In any event, there are only a handful of games that support these features at the moment.