The videocard itself
The videocard itself
Though the graphics card itself is a GeForce GTX 460 with 1024 MB gDDR5 memory running at reference frequency, it of course is a 100% customized model. First lets talk reference specs.
The GeForce GTX 460 series is based on the 2.1 Billion transistor GF104 GPU. The GF104 is a less complicated chip to manufacture as the smaller transistor count directly relates to yields, heat levels, better voltages and thus a better TDP as well. It is a smaller chip to produce.
NVIDIA puts the GF104 chip onto two products, the GeForce GTX 460 with 768MB of graphics memory and the GeForce GTX 460 with 1024MB of memory. For the bigger part of the specification the two are similar when it comes to shader processor count, memory bus and clock frequencies, the 1GB model however definitely will be a good chunk faster, as cutting away 256MB of memory also cuts away a chunk of the ROP engine.
Graphics card | GeForce GTX 460 768MB | GeForce GTX 460 1024MB | GeForce GTX 465 1024MB |
Graphics Processing Clusters | 2 | 2 | 3 |
Streaming Multiprocessors | 7 | 7 | 11 |
Shader processor | 336 | 336 | 352 |
Texture Units | 56 | 56 | 44 |
ROPs | 24 | 32 | 32 |
Core Clock | 675 MHz | 675 MHz | 607 MHz |
Shader Clock | 1350 MHz | 1350 MHz | 1215 MHz |
Memory Data rate | 3600 MHz | 3600 MHz | 3200 MHz |
Graphics Memory | 768MB GDDR5 | 1024MB GDDR5 | 1024MB GDDR5 |
Memory interface | 192-bit | 256-bit | 256-bit |
Memory bandwidth | 86.4 GB/s | 115.2 GB/s | 102.6 GB/S |
Texture Fillrate Bilinear | 37.8 GigaTexels/sec | 37.8 GigaTexels/sec | 26.7 GigaTexels/sec |
Fab node | 40nm | 40nm | 40nm |
TDP | 150 Watts | 160 Watts | 200 Watts |
Okay, so back to the two reference SKUs, we can break down real simple:
- GeForce GTX 460 768MB - 336 Shader processor - 56 TMUs - 24 ROPs - TDP 150W
- GeForce GTX 460 1024MB -336 Shader processor - 56 TMUs - 32 ROPs - TDP 160W
The KFA2/Galaxy GTX 560 WHDI card is a 1024MB model, it runs in a reference setup and is clocked at 675 MHz on the core frequency, and in NVIDIA's typical 1:2 setup mode 1350 MHz on the 336 shader processors.
We'll actually test this with the WHDI card as well, but there is a lot of overclocking headroom on the board as 825 MHz should not be an issue (without voltage tweaking). The gDDR5 memory will be clocked at a slightly shy 3.6 Gbps which is 3600MHz effective (quad data rate).
For your reference, the 768MB versions makes use of three 64-bit memory controllers which boils down to 192-bit memory, and the 1024 GB model has one extra cluster of 256MB attached to it, which requires one more 64-bit memory controller and so this one operates at 256-bit memory bus width.
Anyway, talk is cheap, let's go have a look at what we are talking about today in a nice product gallery, describing some of the features a little better.