AMD's yet-to-be-announced Radeon HD 4890 has been caught on camera, had its specification detailed and managed to appear at retail, too.
Given the nature of the hugely-competitive graphics market, AMD's arch-nemesis NVIDIA won't be letting the Radeon HD 4890 hog all the limelight and will be firing its retort in the form of the GeForce GTX 275.
The card is, of course, yet-to-be-announced by NVIDIA, but as is often the case, its specification appears to have made its way online. Judging by the information we've already seen floating around, here's how the AMD Radeon HD 4890 and NVIDIA GeForce GTX 275 slot in to the existing mid-to-high-end line up:
| Graphics cards | NVIDIA GeForce GTX 295 | NVIDIA GeForce GTX 285 1,024MB |
NVIDIA GeForce GTX 280 1,024MB | NVIDIA GeForce GTX 275 896MB* | NVIDIA GeForce GTX 260 896MB | AMD Radeon HD 4870 X2 2,048MB | AMD Radeon HD 4850 X2 2,048MB | AMD Radeon HD 4890 1,024MB* | AMD Radeon HD 4870 512MB | AMD Radeon HD 4850 512MB |
|---|---|---|---|---|---|---|---|---|---|---|
| PCIe | PCIe 2.0 | |||||||||
| GPU(s) clock | 576MHz | 648MHz | 602MHz | 633MHz | 576MHz | 750MHz | 625MHz | 850MHz | 750MHz | 625MHz |
| Shader clock | 1,242MHz | 1,476MHz | 1,296MHz | 1,404MHz | 1,242MHz | 750MHz | 625MHz | 850MHz | 750MHz | 625MHz |
| Memory clock (effective) | 1,998MHz | 2,484MHz | 2,214MHz | 2,322MHz | 1,998MHz | 3,600MHz | 1,986MHz | 3,900MHz | 3,600MHz | 1,986MHz |
| Memory interface and size | 448-bit (per GPU), 1,792MB, GDDR3 | 512-bit, 1,024MB, GDDR3 | 512-bit, 1,024MB, GDDR3 | 448-bit, 896MB, GDDR3 | 448-bit, 896MB, GDDR3 | 512-bit (2x 256-bit), 2,048MB, GDDR5 | 512-bit (2x 256-bit), 2,048MB, GDDR3 | 256-bit, 1,024MB, GDDR5 | 256-bit, 512MB, GDDR5 | 256-bit, 512MB, GDDR3 |
| DirectX/ Shader Model | DX10, 4.0 | DX10, 4.0 | DX10, 4.0 | DX10, 4.0 | DX10, 4.0 | DX10.1, 4.1 | DX10.1, 4.1 | DX10.1, 4.1 | DX10.1, 4.1 | DX10.1, 4.1 |
| Vertex, fragment, geometry shading (shared) | 480 FP32 scalar ALUs, MADD dual-issue + MUL (unified) | 240 FP32 scalar ALUs, MADD dual-issue + MUL (unified) | 240 FP32 scalar ALUs, MADD dual-issue + MUL (unified) | 240 FP32 scalar ALUs, MADD dual-issue + MUL (unified) | 216 FP32 scalar ALUs, MADD dual-issue + MUL (unified) | 1,600 FP32 scalar ALUs, MADD dual-issue (unified) | 1,600 FP32 scalar ALUs, MADD dual-issue (unified) | 800 FP32 scalar ALUs, MADD dual-issue (unified) | 800 FP32 scalar ALUs, MADD dual-issue (unified) | 800 FP32 scalar ALUs, MADD dual-issue (unified) |
| Multi-GPU | SLI - quad | SLI - three-board | SLI - three-board | SLI - three-board | SLI - three-board | CrossFire - two-board | CrossFire - two-board | CrossFire - four-board | CrossFire - four-board | CrossFire - four-board |
| Hardware-assisted video-decoding engine | NVIDIA's PureVideo HD - full H.264 decode and partial VC-1 decode, plus dual-stream decode | AMD UVD 2 - full H.264 and VC-1 decode, plus dual-stream decode | ||||||||
| Reference cooler | dual-slot | dual-slot | dual-slot | dual-slot | dual-slot | dual-slot | dual-slot | dual-slot | dual-slot | single-slot |
| *rumoured product and specification | ||||||||||
Both cards are believed to be going head to head sometime next month, and judging by the rumoured specification, the GeForce GTX 275's GPU appears to be a higher-clocked derivative of the GPU found in the class-leading GeForce GTX 295.
Judging by NVIDIA's naming choice, we're expecting performance to be somewhere between the GeForce GTX 280 and the 216-core GeForce GTX 260.
