DCS World and Crossfire

[Kenta]

Now that things are getting serious and ED released the new DCS World 1.2.0 I was wondering (I'm aware that this is more of an AMD issue and they should be bugged about it, not ED) if Crossfire support will be added in the near future?

 

I'm getting sick of only have to run this game on one Radeon 6870 and leaving the other graphics card off.

 

Am constantly thinking about selling these two cards and buying a single GTX 680.

 

Does ED have any say to AMD about crossfire?

[whitehot]

I feel ya. I tried to bring up the issue aswell several times both here and @ amd. Sadly, the most detailed reply i could read was about two lines saying that this sim engine will never support crossfire or sli. Something about missing "empty cpu cycles not available for sli" (which, if I have to say, seems pretty silly to me). I have a 6990 hence i have to run dcs like a 6970. What puzzles me is that we get perfect crossfire scaling for games like dirt showdown, which don't need it anyway; while we can't enable it on demanding engines who'll benefit the most. Call me conspiracy but I'm willing to bet there's some distorted commercial logic behind this

[Kenta]

I think I've read somewhere on the forums that this engine problem might change with the new engine that will come with Nevada. Can someone confirm this?

[CeC]

I Don't know...

But I would like to see crossfire implemented too. Too bad to have a gpu that is not used.

[BIGNEWY]

sold my other card after trying to get crossfire to work with no success.

 

Would be nice, maybe you will have better luck with the Nevada map when it comes out

[joey45]

The engine ATM is more dependent on CPU not GPU.

 

Games like DiRT is more dependent on GPU not CPU.

[atledreier]

Went from 6990 to a 680. NEVER looking back. Performance has increased everywhere, adn zero hassle and jumping through hoops to wring out performance.

[Novum]

i gave up two cards when i tested my 8800GT

 

However i do like to se the game engine take advantage of GPUs, since they can be 100x faster then a cpu in some areas

[woofer15]

Who designs an engine to rely more heavily on CPU than GPU?! This isn't 1993 -- I'm not running this on a Tandy system that's entirely CPU-dependent (more importantly, there's no longer a TURBO button...:)).

 

My issues precisely exemplify the CPU heavy issue (AI must cycle heavy on CPU in campaign, for example):

http://forums.eagle.ru/showthread.php?t=94419

 

I can't get this sim to run on my pretty decent system in the campaign....I WAS thinking of upgrading to crossfire 6870s to squeeze out some FPS until I ran into all these posts saying it won't even utilize the second card.....based on my experience, I'm not having GPU issues anyways (no major difference between FPS with HIGH v. LOW graphics settings in campaign).

 

What a joke.......must be one of the one (if only) games on PC that doesn't get an FPS boost from DOUBLE the GPU power.

[EtherealN]

Who designs an engine to rely more heavily on CPU than GPU?! This isn't 1993 -- I'm not running this on a Tandy system that's entirely CPU-dependent (more importantly, there's no longer a TURBO button...:)).

 

Do you know exactly why GPU's are so powerful at what they do?

This is not simply about "designing an engine". Different types of jobs will, by their nature, require specific types of calculations. Different types of processors are differingly qualified to handle different types of calculations.

 

The problem with moving things to the GPU is that GPU's are actually very slow. Their advantage is that they are very wide, meaning that they can do a LOT of things at the same time. When you do something like shade a bunch of pixels on a screen, this is usually not a problem since those pixels can be handled as units; you don't have to worry much about the pixel next to it.

 

But not all software jobs are like that. The biggest issue is when you have dependent data; that is, when you have a lot of calculations to do, but each calculations is dependent on the result of a previous calculation. Stuff that into a GPU and it'll sit there and pretty much do nothing, because most of the execution resources will just sit there waiting.

 

What a joke.......must be one of the one (if only) games on PC that doesn't get an FPS boost from DOUBLE the GPU power.

 

I take it you are not a software engineer?

 

Most computer games are, relatively speaking, all graphics and not much else. (Sure, there's fancy windowdressing like PhysX as well.) You need to realize that, in order for an increase in graphics processing power to have effect, the GPU needs to be told what it is to draw. This information is also sent out in "frames", and if your CPU is unable to perform simulation faster than 30 frames per second, then no matter what kind of graphics resources you have you simply will not get more than that, because your GPU(s) won't have anything to paint.

 

And no, you cannot just move any type of calculation over to the GPU. There's a reason why things like Folding@Home is so rediculously better on a GPU, they are by their nature extremely parallellized types of computation - just like graphics rendering is. For every thing that is by nature parallell, there's other things that are by nature data dependent and serial in nature, and then things change.

 

If GPU's are automatically better, why do we still have CPU's in our computers? (Yes, there are full OSes that can be run on a GPU alone, but there's a reason why those are novelties only - amusing hacks implemented by nerds with too much time on their hands - rather than actual production operating systems.)

[woofer15]

Thanks for the thorough answer.

 

Great, so I have a 3.7Ghz quad core CPU…why design a game such that its so CPU heavy and GPU independent that I can run it perfectly unless I'm playing the campaign or any other mission with tons of units?

 

This is the 2nd time I've purchased DCS A10C…I hear the newer patches to DCSW slammed FPS for many - I'm sure that you can understand the frustration of people who exceed RECOMMENDED requirements but cannot play the main portions of the sim…it's false advertising - and it isn't even a "relatively" cheap/easy fix like buying a GPU…I need a super CPU 10X more powerful than the rec specs I guess?

[woofer15]

And you're right! :) I'm definitely not a software anything - I do not know d**k about computers. I'm dumb guy in the military and also a civie pilot. When I buy stuff to play on the computer, and my system exceeds specs, I just want it to work…

[Revelation]

Thanks for the thorough answer.

 

Great, so I have a 3.7Ghz quad core CPU…why design a game such that its so CPU heavy and GPU independent that I can run it perfectly unless I'm playing the campaign or any other mission with tons of units?

 

This is the 2nd time I've purchased DCS A10C…I hear the newer patches to DCSW slammed FPS for many - I'm sure that you can understand the frustration of people who exceed RECOMMENDED requirements but cannot play the main portions of the sim…it's false advertising - and it isn't even a "relatively" cheap/easy fix like buying a GPU…I need a super CPU 10X more powerful than the rec specs I guess?

 

Trust me, we all want DCS to be multi-threaded out the rear and support multiple GPUs/CPUs. That will come in time, just like the sound engine was moved to a separate core, more stuff will as well. It takes time...

 

ED has stated that their goal is to make DCS multi-threaded but they didn't want to scrap the entire engine and rebuild it from scratch. The man-hours and shear cost would be way too high for a small studio to go down that path.

 

*IF* ED went down that path we would still be waiting on DCS A-10C beta...

 

Why did you buy DCS A-10C twice?

[woofer15]

Well, I bought A10C about a year and a half ago (around the release, I guess?)...but had the same type of issue - put simply: met the specs but game failed to work. Had a 32-BIT OS and it CTD'd even after all the GB switches and other tweaks. So, I gave up after a month and asked for refund. Now, coming back a 18 months later (I upgraded my OS to 64bit for some of my wife's adobe software for her job), and I purchase again...

 

Don't get me wrong, I really appreciate everyone's help - I'm on these forums because you guys know everything and I know nothing....but, now it looks like I'm exceeding specs again and being told (essentially) to buy an entirely new PC (or wait another 18 months?). Like I said, I'm dumb. So, I can install a new GPU...but not rebuild an entire new motherboard and CPU and whatever else comes with that!

 

It just reminds me of the old days of MS-DOS and Win 3.11 --- it was so frustrating to get everything to work out-of-the-box (this isn't that bad, at least!), but nowadays it seems most products do...but not this one.

[Revelation]

Well, I bought A10C about a year and a half ago (around the release, I guess?)...but had the same type of issue - put simply: met the specs but game failed to work. Had a 32-BIT OS and it CTD'd even after all the GB switches and other tweaks. So, I gave up after a month and asked for refund. Now, coming back a 18 months later (I upgraded my OS to 64bit for some of my wife's adobe software for her job), and I purchase again...

 

Don't get me wrong, I really appreciate everyone's help - I'm on these forums because you guys know everything and I know nothing....but, now it looks like I'm exceeding specs again and being told (essentially) to buy an entirely new PC (or wait another 18 months?). Like I said, I'm dumb. So, I can install a new GPU...but not rebuild an entire new motherboard and CPU and whatever else comes with that!

 

It just reminds me of the old days of MS-DOS and Win 3.11 --- it was so frustrating to get everything to work out-of-the-box (this isn't that bad, at least!), but nowadays it seems most products do...but not this one.

 

What I would recommend, if you played with exceptable framerates before, keep running the auto updater and the issues in performance will get fixed. Hopefully sooner rather than later for those that are experiencing performance issues that make it unplayable.

[woofer15]

What I would recommend, if you played with exceptable framerates before, keep running the auto updater and the issues in performance will get fixed. Hopefully sooner rather than later for those that are experiencing performance issues that make it unplayable.

 

Actually, I've never had acceptable frame rates in most campaign missions in some single player missions (seems to be a not uncommon problem based on forums). AI/scripting related issue? http://forums.eagle.ru/showthread.php?t=94419

http://forums.eagle.ru/showthread.php?t=91108

 

Although I did read about the FPS drop you're likely referring to (from 1.2.0 to 1.2.1); so I'm going to hold off on updating for a bit.

 

 

Thanks for your time!

 

EDIT: although I did notice that you have a 3.2GHZ CPU in your posting....do you not have issues with low FPS in most campaign missions in 1.2.0 DCSW? Other than that, we have similar setup.

[Revelation]

I rarely fly on my 3.2GHz machine these days. I also rarely saw dramatic slow downs with the old machine.

 

The bottom machine, the one I use now, really doesn't have a lot of issues.

[AtaliaA1]

@ EtherealN Now that was a complete answer. I like reading things like that always looking to learn.

 

So inline with the direction of your synopsis. There are things, from an engineering standpoint that could binifit this software.

 

Just for reference what are they? simply putting the ILS and other systems on another core? or would there be more to it?

[Darkwolf]

And here is another pissed off crossfire customer, me. Just bought crossfire and two GPU for nothing. I got shitty texture result.

 

Before going further in the expense... If i disable Crossfire in the AMD software, will I be able to use 4 screen with only 1 GPU running ??

Is there another solution that I can use to get 3 screens for panels and home made HUD and 1 for outside world ?

[Panzertard]

@ EtherealN Now that was a complete answer. I like reading things like that always looking to learn.

 

So inline with the direction of your synopsis. There are things, from an engineering standpoint that could binifit this software.

 

Just for reference what are they? simply putting the ILS and other systems on another core? or would there be more to it?

 

You can read more about it here, follow what c0ff is replying to.

http://forums.eagle.ru/showthread.php?t=104441&page=2

[westr]

DCS runs with crossfire on my PC has been for a while now but it took me a long time to get it working. I have had this discussion with a few people. If set to alternate frame rendering I can get both cards running I have no problem with the game either. I can't say for sure it will work for you but i cant see why it shouldnt I do know my suggestion worked for at least one other forum user. I did use a software called radeon pro but since 1.2.5 this has stopped working for me however I'm still able to force alternate frame rendering in DCS with a DCS profile through the catalyst control centre

[Avernus]

i attempted to Cfx my previous 6970 cards with a strange result

 

Cfx was working, However it was scaling Negative.

That is, 2 gpus = lower minimum framerate

Played with Radeonpro a lot, no luck

 

New system with 2x nvidia gtx670 cards sli scales extremely well.

[woofer15]

DCS runs with crossfire on my PC has been for a while now but it took me a long time to get it working. I have had this discussion with a few people. If set to alternate frame rendering I can get both cards running I have no problem with the game either. I can't say for sure it will work for you but i cant see why it shouldnt I do know my suggestion worked for at least one other forum user. I did use a software called radeon pro but since 1.2.5 this has stopped working for me however I'm still able to force alternate frame rendering in DCS with a DCS profile through the catalyst control centre

 

Thanks for suggestion, I've changed my CCC to "AFR Friendly" on the Crossfire and will let you know if I see any improvement!

[Mustang]

Has anyone here tried the 13.8 Catalysts with the Xfire frame pacing and DCS?

[westr]

 

I recently downloaded CCC 13.8 and found crossfire no longer worked. I had to delete my CCC and re-install 13.4 and re-create a DCS World profile.

I now have a AMD Crossfire logo in the top right hand corner of my start-up screens...:)