ATI MultiGPU Done Right: The Radeon X1800 CrossFire Edition
by Derek Wilson on December 20, 2005 9:00 AM EST- Posted in
- GPUs
The New Improved CrossFire
With the X1800 series of CrossFire cards, we will finally be able to test resolutions above 1600x1200. When it comes to multiGPU solutions, the more flexibility the user gets, the better. It is difficult to justify dropping over a thousand dollars on a setup that has limitations, and the removal of the single-link TMDS receivers definitely makes this version of CrossFire a more viable solution than its first incarnation in the X800 series.
The addition of dual-link TMDS receivers on the master card marks the biggest upgrade we see on the X1800 version of CrossFire. With a new dongle connector, and the improved bandwidth of dual-link DVI, ATI has given their customers what they need to power huge resolutions. We will still be limited in performance on a game by game basis, as alternate frame rendering (AFR) is still the most efficient (and most restrictive) multiGPU mode in which to work. While ATI's Scissor and SuperTiling modes offer some flexibility and the extended SuperAA modes offer an alternate way to add value to games (enhancing quality rather than performance), there are some caveats we will mention in our performance analysis (in particular with Black and White 2).
The basic features of CrossFire haven't changed from the initial design. For a refresher on CrossFire, check out our previous articles on the subject. Aside from the TMDS upgrades, ATI has refreshed their compositing engine with a larger FPGA from Xilinx. This allows ATI to composite the larger images possible with dual-link DVI input. Most of the rest of the CrossFire hardware is either unchanged or only slightly altered. From a board layout stand point, it would certainly make more sense if ATI were to build GPU to GPU communication into their parts as NVIDIA has done with SLI. Incorporating a silicon version of their compositing engine onto their GPUs would save board space and could improve performance even more.
From a high level, the X1800 CrossFire edition can be paired with a regular X1800 XT or an X1800 XL. There isn't a cheaper CrossFire card for the cheaper X1800 XL, and in order to get CrossFire setup and running with the X1800 XL, half of the RAM on the card needs to be disabled. In order to disable the RAM, the system needs to be rebooted, but in other cases CrossFire can be enabled and disabled without rebooting. While adding a CrossFire card to one's existing X1800 XL setup will definitely increase performance, it is ends up delivering even less for your money than when pairing it with an X1800 XT. The price tag is already a bit hefty, and we expect that most people who want this card will be those who need the absolute maximum performance possible. The value of CrossFire as an upgrade won't really be worth it unless the price of the X1800 CrossFire card comes down quite a bit.
With the X1800 series of CrossFire cards, we will finally be able to test resolutions above 1600x1200. When it comes to multiGPU solutions, the more flexibility the user gets, the better. It is difficult to justify dropping over a thousand dollars on a setup that has limitations, and the removal of the single-link TMDS receivers definitely makes this version of CrossFire a more viable solution than its first incarnation in the X800 series.
The addition of dual-link TMDS receivers on the master card marks the biggest upgrade we see on the X1800 version of CrossFire. With a new dongle connector, and the improved bandwidth of dual-link DVI, ATI has given their customers what they need to power huge resolutions. We will still be limited in performance on a game by game basis, as alternate frame rendering (AFR) is still the most efficient (and most restrictive) multiGPU mode in which to work. While ATI's Scissor and SuperTiling modes offer some flexibility and the extended SuperAA modes offer an alternate way to add value to games (enhancing quality rather than performance), there are some caveats we will mention in our performance analysis (in particular with Black and White 2).
The basic features of CrossFire haven't changed from the initial design. For a refresher on CrossFire, check out our previous articles on the subject. Aside from the TMDS upgrades, ATI has refreshed their compositing engine with a larger FPGA from Xilinx. This allows ATI to composite the larger images possible with dual-link DVI input. Most of the rest of the CrossFire hardware is either unchanged or only slightly altered. From a board layout stand point, it would certainly make more sense if ATI were to build GPU to GPU communication into their parts as NVIDIA has done with SLI. Incorporating a silicon version of their compositing engine onto their GPUs would save board space and could improve performance even more.
From a high level, the X1800 CrossFire edition can be paired with a regular X1800 XT or an X1800 XL. There isn't a cheaper CrossFire card for the cheaper X1800 XL, and in order to get CrossFire setup and running with the X1800 XL, half of the RAM on the card needs to be disabled. In order to disable the RAM, the system needs to be rebooted, but in other cases CrossFire can be enabled and disabled without rebooting. While adding a CrossFire card to one's existing X1800 XL setup will definitely increase performance, it is ends up delivering even less for your money than when pairing it with an X1800 XT. The price tag is already a bit hefty, and we expect that most people who want this card will be those who need the absolute maximum performance possible. The value of CrossFire as an upgrade won't really be worth it unless the price of the X1800 CrossFire card comes down quite a bit.
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tuteja1986 - Tuesday, December 20, 2005 - link
i meant to say BF2 :( i know i am an idiot >>> Anyways please forgive me and i have a 7800GTX so don't call me a ATI fanboy , i can even take a screenshot if you want :!tfranzese - Tuesday, December 20, 2005 - link
So were back here today with the CrossFire solution that should have been: the ATI Radeon X1800 CrossFire Edition.we're
tfranzese - Tuesday, December 20, 2005 - link
So lets all throw a shit fit about every company that ever announced a product only to have availability weeks to years from that announcement.Anandtech staff is just as bad as it's two year old readers who tie emotions in with silicon. Grow up and learn some patience - if you can't wait, buy someone elses product and stop your whining.
tuteja1986 - Tuesday, December 20, 2005 - link
crossfire does great in DOD source , Black and White 2 and it beats Nvidia 7800GTX 512MB SLI . how ever it doesn't great in DOOM 3 engine. FEAR and Chaos theory it manages to defeat the 7800GTX 256MB SLI easy but in high quality of chaos theory it keeps up with 7800GTX 512MB. X1800XT crossfire has only one problem and that it suck in DOOM engine benchmark but overall its great.jonny13 - Tuesday, December 20, 2005 - link
"crossfire does great in DOD source , Black and White 2 and it beats Nvidia 7800GTX 512MB SLI "You obviously didn't read the article if you thought Crossfire did great in Black and White 2. It failed to get above 12 fps and was over 50% slower than a single x1800XT at times.
BigLan - Tuesday, December 20, 2005 - link
No x1800 master cards showing on Newegg or CompUSA's website as of 10AM EST. Really hope ATi make good on their availability promises this time.michaelpatrick33 - Tuesday, December 20, 2005 - link
I think the R580 chipset and videocard will be the real crossfire shot at SLI. This feels a little early generation SLI to me and they seriously need to get rid of the dongle, LOL. I can't wait to see the R580 in relation to the 7800GTX 512 market edition card.radekhulan - Wednesday, December 21, 2005 - link
Problem is that current ATI Crossfire setup is way inferior to NVIDIA SLI, despite big heading "ATI MultiGPU done right", and I do not believe this will change much with hyped R580.With NVIDIA I can:
- mix any similar cards, being it 6800GS/GT, 7800GT, 7800GTX, 7800GTX-512, thus saving costs
- get much better drivers
- get support for user defined game profiles, thus when I purchase a new game, I do not have to wait a month or two for card producer to come up with new drivers and that game support (ie. with ATI I will play new games using SuperTiling with 0% to -50% "improvement", with NVIDIA I will create a new game profile using e.g. AFR2 and get immediate 90% improvement)
- there is no huge external dongle, and I guess picture quality should be better as well with SLI
- there is much better availibility of NFORCE4-SLI chipsets / motherboards
- I can connnect up to 4 monitors to NVIDIA SLI, but I cannot to Crossfire
- I can switch NVIDIA SLI on/off without restart
- I get better performance with NVIDIA SLI
ATI Crossfire seems still like an afterthought, nothing else, while NVIDIA SLI is a technology incorporated into the core. If I want to game on 1600x1200, the only real option is to get NVIDIA SLI.
I understand that Anandtech cannot bash Crossfire too much, to keep good relations with ATI, free products, shows, trips, etc., but I belive that superiority of NVIDIA SLI is very clear here..
Visual - Thursday, December 22, 2005 - link
I don't know what you're talking about.- you can't mix any of the cards you listed with each other, except a GTX with a GTX512 (gotta use only 256mb from each, and run the 512 model at the normal GTX speeds);
- dont see how drivers are better
- dunno if a profile tool/editor for ati exists or is in the making, so cant comment on this; but you're overestimating the improvement on nvidia
- its just a cable; your guess about the quality comes from what grounds? guess what, you guessed wrong.
- point, unless you go intel; but i seriously hope both ATI and nVidia will release unlocked crossfire drivers that work on any dual16x board
- last i checked, you can't use the outputs on the secondary card in SLI mode, you have to switch SLI off first; i might be counting on outdated information, but i doubt it.
- yeah, and you do that how often? i bet its much fun and enjoyment... no seriously, you're right that this is a convenient feature as occasionally you'd have to switch it, but it doesnt seem too important does it? plus there's no telling if crossfire can't do the same eventually.
- again an unfounded claim
Indeed Crossfire seems like an afterthought to me too, and nVidia's superiority here is (atleast was, until recently) clear. But that's the good part of competition - nVidia forced ATI to "afterthink" something out, and it will be getting better with time. Crossfire is just as serious an option as SLI, and if you stick with your "the only real option is to get NVIDIA SLI" you're just purpously closing your eyes.
Think what you want, I don't really care. But don't preach unfounded fanboyism without expecting to face differing oppinions.
coldpower27 - Tuesday, December 20, 2005 - link
However, 7800 GTX 512 is not the competitor for R580, that competitor is G71, which is supposed to be due in Early Feburary as opposed to R580's Late January.