NVIDIA’s DirectX 11 Architecture: GF100 (Fermi) In Detail
Texture Filtering
As with anti-aliasing, there have been improvements made to texturing too. Interestingly the GF100 only has 64 TMUs, which is much less than the 80 TMUs on the GTX285, but nVidia claims overall performance should still be higher because of improvements to performance and efficiency.
Texture caching has been substantially improved, with the L1 cache being redesigned for greater efficiency. Also the presence of a unified L2 cache means the texture cache size is three times higher than on the GT200.
Layout changes and internal improvements to the texture units also combine with a higher TMU clock speed. On the GT200 the TMUs ran at the GPU’s core clock; on the GF100 they run at a higher clock, which allows them to perform more work in the same amount of time. nVidia’s numbers show 40% to 70% higher texturing performance than the GT200, despite having much fewer TMUs.
The GF100’s texture units also offer hardware accelerated jittered sampling. This essentially means the hardware has the ability to offer a form of stochastic filtering by varying the texture sampling on a per-pixel basis. This is done by implementing DirectX 11’s Gather4 in hardware, and it provides the ability for up to four texels to be fetched from a 128×128 pixel grid with a single instruction.
This not only improves performance with things like ambient occlusion, but it can also improve image quality by removing banding through random sampling. It also allows game developers to implement customized texture filtering more efficiently. nVidia states that the GF100’s hardware implementation of this technique offers up to twice the performance of the GT200.
ati status
[told] x
benchmarks? none?
Benchmarks in a review of brand new GPU architecture!?!
– when have you seen that before?
We expect to have benchmarks vs. GTX 285 and vs. Radeon when we get the actual cards.
I noticed that you mentioned “time check”. These comments must be approved manually; sorry for any delay.
I thought you guys guys were gonna post something substantial, not this rehash. NDA my ass…
This is what they gave us TTimmy. It is not like other sites got anything different and we got garbage.
However, I do understand that this is not what you all wanted to see. We also wanted to see some more definitive information such as benchmark numbers, clock speeds, release date and pricing but…ABT isn’t releasing a video card (yet), they are.
I wouldn’t call what we posted, a “rehash”. What has happened with this progressive revelation, always happens with new architecture – no matter who releases it, AMD, NVIDIA or Intel. First you get the general information about upcoming architecture, then more and more information is released until it goes into production.
Much of the information about Fermi’s GeForce in our article is brand new information about Fermi’s gaming capabilities. Much of what we wrote about was not disclosed anywhere previously. There is a lot more to add since we wrote about Fermi’s computing architecture last year.
As I understand it, only the devs would have engineering samples of GF100. That means NVIDIA’s partners would not have them nor would any tech review site. There are no fixed clocks, nothing about power consumption nor thermals – and certainly no solid performance benchmarks other than what NVIDIA did internally. Not yet.
I hope Nvidia release a decent mid range $300 Fermi GPU.