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In Theory: Tessellation And Bitstreaming

Nvidia GeForce GTX 460: The Fermi We Were Waiting For
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So, we’ve established that a 675 MHz GF104 with 336 CUDA cores is often faster than a 607 MHz GF100 sporting 352 cores. Beyond that, the GF104-based card is less expensive, cooler, and more power-friendly. Why on earth would anyone spring for the GeForce GTX 465 at this point?

The only reason we can see would be future-proofing. You see, by smashing more cores into each SM, Nvidia makes it possible to enable GF104 using fewer SMs. Fewer SMs means fewer PolyMorph engines—the fixed-function hardware used to bolster geometry performance, making DirectX 11’s tessellation capability more palpable.

With the cut-back GF100 in GeForce GTX 465, you have 11 PolyMorph engines active and five disabled. The GF104 offers seven active engines in each of the GeForce GTX 460 cards. The result of that haircut is evident in running the Unigine 2.1 benchmark with Extreme tessellation at 1680x1050.

As you can see, frame rate scales fairly well according to the number of SMs available. Even the “handicapped” GF104 is able to best AMD’s clearly-bottlenecked Radeon HD 5850 by a fair margin, though.

In the future, it might turn out that actual playable games use this level of tessellation, in which case the GeForce GTX 465 will rise up in front of the GTX 460s. But when it comes to the $199 price point, I have to postulate that a majority of folks buy for the performance they see today, which makes all of this discussion about tessellation a little less relevant.

If you want to see what’s being done with tessellation today, check out our Aliens vs. Predator benchmark page. There you’ll see the GeForce GTX 465 and 460 1 GB head-to-head, with the GTX 460 turning in faster frame rates with anti-aliasing enabled.

GF104 In The Home Theater: Nvidia Joins The Party

One of the advantages we’ve been giving AMD’s Radeon HD 5000-series cards has been the ability to send unmolested Dolby TrueHD and DTS-HD Master Audio soundtracks from Blu-ray movies over HDMI to a stereo receiver for decoding—a process referred to as bitstreaming. Enabling it requires a protected audio and video path, a secure line guaranteed inaccessible to someone snooping the bus (for DRM reasons).

Incidentally, after AMD implemented its PAVP, Intel did the same with its Clarkdale- and Arrandale-based Core i5/i3 CPUs.

Nvidia is a little late to this party, but when the GF100 emerged without a PAVP of its own, we thought we’d never see support in this product generation. The company is proving us wrong with GF104. Armed with a revised video processor (though still referred to as VP4), the GPU can now handle bitstreaming high-def audio.

The unfortunate rub is that the current driver doesn’t support it. We were able to get Dolby Digital/DTS across HDMI, along with multi-channel LPCM, but no Dolby TrueHD or DTS-HD. And even when the feature is enabled, it’ll take buying a copy of CyberLink’s PowerDVD 10 playback software to support it. Frankly, this is a bummer for anyone who made the jump to PowerDVD 9 as AMD and Intel enabled bitstreaming in their graphics products and is now considering a Fermi-based board. We’d really like to see a patch to make this possible in PowerDVD 9.

With that said, we waited through several drivers and patches for AMD to get its bitstreaming support dialed-in, so it’s not something we’ll hold against Nvidia right out of the gate. I’m just excited to see more mainstream versions of the Fermi architecture become viable in a gaming- or Blu-ray 3D-oriented HTPC. For now, my Radeon HD 5770 remains…

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  • 1 Hide
    wild9 , 12 July 2010 12:32
    Nice read: clear, subjective and interesting.
  • 1 Hide
    riot91 , 12 July 2010 14:34
    Good card I might consider for my next upgrade
  • 0 Hide
    riot91 , 12 July 2010 14:34
    Good card I might consider for my next upgrade
  • 3 Hide
    pentabuksus , 12 July 2010 16:22
    Good review

    but why can't i enter the contest in europe? I do have a steam account...
    and i'm viewing the UK version of the site...
  • 0 Hide
    blacksheep101 , 12 July 2010 23:35
    Great article, well written. I think 2 x 460 coudl be in the horizon as i'm one of the smug people who didn't go for the 465 :-)

    Quick question, any ETA on the SLI article? Please please please?
  • 0 Hide
    Anonymous , 13 July 2010 01:03
    The 460 is selling for a very respectable £150 on ebuyer.com right now. A definite purchase for my new casual gaming rig!
  • 0 Hide
    chechak , 13 July 2010 04:40
    guys you talking about GeForce GTX 465 or GeForce GTX 460?
    XD
  • 1 Hide
    Anonymous , 13 July 2010 10:16
    phooey on the US only competition, a steam key isnt something you have to ship. You have readers around the world; take advantage of it!
  • 0 Hide
    ksampanna , 13 July 2010 14:58
    At last, a Fermi that I don't actually hate
  • 1 Hide
    Anonymous , 13 July 2010 16:13
    Too bad it`s about half year late..
  • 0 Hide
    13thmonkey , 13 July 2010 18:44
    can you please consider running benchmarks of initial release drivers vs latest drivers in a few months time so we could see what the actual improvement is, and perhaps compare that to the 6month drivers for the red team?
  • 0 Hide
    aztec_scribe , 14 July 2010 15:59
    I'm waiting to see how much faster this is than a GTX 275, at the moment the Hierarchy Chart has me confused as the 465 is on the same level as my 275. so I presume if I sell my 275 use that money and add say £40 more and buy the 1GB 460 I'd be going down in performance but I'd be gaining DX11! Is that really worth it?
  • 0 Hide
    psiboy , 16 July 2010 21:42
    um whats with 5770 beating 5850.... That doesn't sound right (and I own a 5770 lol) are these benchmarks correct?
  • 0 Hide
    Anonymous , 18 July 2010 13:13
    Any idea about compute performance?
    I was wondering about ray-tracing performance with programs like Bunkspeed Shot, which can use Nvidia GPUs to do ray-tracing.

    If it works well, then this might be a good poor-man's compute GPU.