CoH and Crossfire

at this time CoH is not accelerated by default on any Multi-GPU setup.

You can force an alternate frame rendering mode, but in most cases this will cause client instability.

Any description on how to enable crossfire support in CoH?

No.

Maybe I should make this a little bit clearer. Modifying components of atiogl can, and more than likely will, result in a hard kernel crash and loss of data. Now if you happen to LIKE reinstalling Windows, by all means, feel free to try and edit the atiogl.xml or the atiogl.dll files.

That is pretty much always the best option.

I wouldn't go... that far yet.

Television has been playing around with Multi-GPU rendering modes on the backend of the game. There already have been some substantial visual performance gains from the SLI test back during I17 Beta. E.G. I was able to run medium ultra-mode settings on SLI'd GTS 250's.

Warning Tangent: You can still force AFR SLI now by using tools like nHancer and modifying Hex values. This approach isn't really recommended, even though it's not as hazardous as messing with .dll's directly, messing with the hex values can cause some nasty damage to your system. I don't mean damage like memory corruption resulting in having to reload stored data. I mean physical damage such as one GPU doing too much work and not obeying a load balancer. It is possible when mucking about with the functions of multi-gpu rigs to send one GPU's usage skyhigh and give it too much work, and burning out. It's also possible to electrically burn out the SLI bridge.

Just take a moment and browse through some of the posts here on these forums, and those on the Starcraft II forums. You have people out there who honestly believe that the software application can drive a GPU into an overheat mode. Yes, badly written software can overheat a GPU. Case in point, Nvidia's software driver that disabled all thermal controls.

For the most part, overheating is not a a software problem. It is a hardware problem. All external graphics cards are built to run at specified clock speeds, and each is theoretically built to exhaust a certain amount of heat. If your graphics card is, gasp, overheating: either you don't have enough case heating; the graphics card wasn't built properly in the first place; or you've been messing with how the hardware works. Mucking about with the load-balancers in multi-gpu rigs and forcing different methods of pushing the graphics cards can result in permanent physical damage to the computer.

This is why Crossfire and SLI profiles are such big deals from Nvidia and ATI. If they put out a profile, you have a certain amount of trust that they've actually tried that profile out... and if any hardware damage results from using their profile... you have somebody's throat you can go wrap your hands around.

Getting back to the original question: is it better to go single gpu now than buy with multi-gpu in mind? I don't know how to answer that:

I don't know what the time-table looks like for AMD or Nvidia to deliver reliable multi-gpu support with this game. My suspicion is that we'll see AMD deliver support first, since, well, beyond being a graphics partner, they've been much more involved with OpenGL as of late.

I don't know what other games you play. Some benefit drastically from Multi-GPU support. Case in point, GTX 460 2X SLI. In games that can leverage multi-gpu setups, the GTX 460 can shoot-past the RadeonHD 5870 2X Crossfire.

There is no garentee that any game you pick up and play is going to be capable of, or will, leverage a multi-gpu rig. If you want the most guaranteed performance, buy a single card.

Warning - Tangent:Going back to the 460. Yes, it does actually outrun 5870's in 2X Multi-gpu modes on supported games. You would kind of hope that a mid-range part released 10months after a competing high end product would have that kind of performance equalization.

I mean, the RadeonHD 2900 and RadeonHD 3870 were separated by only, something like a 5month window. In May 2007 2900 launched at a $400 price-point. In November 2007 the $180 RadeonHD 3850 came along and promptly put the card that sold for over twice as much in a rubbish bin.

The RadeonHD 3870 and the RadeonHD 4850 were separated by an 8 month window. The 3870 launched with a $220 MSRP in November 2007. In June 2008 the RadeonHD 4850 launched at an MSPR of $200 and had no problems doubling the performance.

The fact that the GTX 460, despite being a mid-range part on a fresh new chip spin from the fab, struggles to best the competitors binned filler card from 5 months prior in single GPU tasks? That's worrying. Honestly, if I was an Nvidia fan, which I'm not, I'd be panicking given that the competitor has said they won't be doing a product refresh... they are just going to go straight to their next generation of chip design.

Actually this is false. The 5870x2 Crossfire does beat the best Nvidia has to offer 480 SLI in many multi-gpu supported games.

http://www.xbitlabs.com/articles/vid...i_8.html#sect1

A lot of it depends on the game, resolution, and driver version.

ATI is notorious for releasing horrible drivers.

Catalyst 10.6 and 10.7 for example offer loads of problems and major drops in FPS for most consumers.

However 10.4 and 10.5 run fantastic for the most part and offer outstanding frame rates.

This is obvious when you compare Techbit's review where they're using ATI Catalyst 10.5 vs. Techspot's review where they are using ATI Catalyst 10.6.


Also the GTX 480 SLI's run at almost 400W *IDLE* that's twice that of 2x 5870 Crossfire cards. They also generate much more heat under full load.


There does tend to be a slight edge for users w/ 480SLI playing at 2560 x 1600, 8x AA, 16xAF but who wants to play games at 40 FPS or lower anyhow? When you get at that resolution you still have to turn off some bells and whistles or you're going to have average frames under 60 FPS which isn't for me.



480 SLI vs. Crossfire 5870 are very competitive with each other in terms of performance.

The key is making sure ATI owners do not run Catalyst drivers 10.6 or 10.7 - wait for 10.8.

Unfortunately that will probably be true lol.