Beyond3D fails to go beyond 3D
..but that's fine by me, because they have written up a very nice look at 3dfx's new VSA-100 products announced at Comdex. As ever, even if you've read five articles on this topic, Beyond3D's article is still worth a look. Here are some of their comments on the VSA-100 architecture's memory inefficiencies in multi-chip configurations:
By using 4 independent chips, the Voodoo5 6000 has each chip deal with ¼ the frame-buffer information. Now, the inherit problem with this is that each chip has dedicated memory (32 MB each in the case of the 6000) and each of these must hold the same textures. It is basically redundant texture memory. Now 3dfx is saying that with texture compression (something they are now strongly evangelizing) and with only dealing holding ¼ the frame-buffer data, you’ll still be doing well overall. While this is true to some extent, you’re still waiting [sic] memory nonetheless. So, if you have to deal with 20 MB of textures, you’re really storing a total of 80 MBs. Really, a considerable waste, though an effective way of improving bandwidth.
I have to wonder how texture tranfers will affect AGP bus traffic in the quad-chip setups, as well. No doubt 3dfx's new baby will be fast, but its design tradeoffs may become serious liabilities.