Suggestion for the 1C Devs

[Damixu]

Hey, don't be stupid and buy SLI/Crossfire GPU combos. Every hardcore, I mean Hardcore game/sim only get worse with those. Those run of the mill sim look-a-likes doesn't count...

My golden rule is to buy always fastest single core GPU available and it works out of the box right away....

[pstyle]

Originally Posted by Damixu

Hey, don't be stupid and buy SLI/Crossfire GPU combos. Every hardcore, I mean Hardcore game/sim only get worse with those. Those run of the mill sim look-a-likes doesn't count...

My golden rule is to buy always fastest single core GPU available and it works out of the box right away....

oooof? I like the use of this vague term "hardcore"... a good way of ensuring you can weasel out of any examples to the contrary by claiming they just aint hardcore enough.
I bought 2 x GTX570s in SLI mode. Worked out of the box right away.. On games that actually support SLI (skyrim for one) it's bloody great.

[Damixu]

Originally Posted by pstyle

oooof? I like the use of this vague term "hardcore"... a good way of ensuring you can weasel out of any examples to the contrary by claiming they just aint hardcore enough.
I bought 2 x GTX570s in SLI mode. Worked out of the box right away.. On games that actually support SLI (skyrim for one) it's bloody great.

Go ahead any fly decisive aerial battles in English channel in year 1940 with Skyrim.

I know most of the major titles in gaming support SLI/Crossfire but strangely several hardcore simulation games doesn't. I suppose it's because sims are quite niche market and the developer companies are very small or limited and they can't affort to program support those dual/trio GPU cards (or does not use ready made gaming enigne which could support out of the box).

edit: Byt the way, I love Skyrim

[Stublerone]

Just waste to use sli, sorry! It seems, that you are really thinking that sli will improve clod performance by far? I say: U only get a big performance increase with sli in clod, if you already have highend cards and start multiple display setups. A sli with mid range cards woulf only help under the circumstance, that your mid range card has 3 gb ram on every card. Otherwise, the tree rendering or other things wouldn't improve that much.

Be aware, that as soon as your card is running out of memory, clod will run insufficient.

I do not know, why some users really think, that sli is good!?! The currently used technique is insufficient until they rethink this whole sli thing and give us a new sli.

Simply dumb to talk about that technology in that state. Never think about sli as a cheap upgrade to get more power. It is just for a small part of the com, who spend a lot of money to max out to the highest possible.

Skyrim is for sure a good game but not comparable. Skyrim for me is casual gaming and the engine is optimized to work for consoles as well. So the load , the memory usage has to be low. Ps3 nearly has no memory. So, all this games never reach the memory usage of a pc sim game. ->That is, why u can really increase performance in skyrim, but not in clod (only with the explained hardware, which is not mid-range in most cases).

[flyingblind]

The OP dose have a point. I have a mid-range card with 1GB memory and at least wish I had got a 2GB version. The best option for me would be to buy a second matching card if only I could be sure that would work properly. Do I waste the first card and go for a better single GPU or do I risk wasting more, albeit a smaller amount of money on a SLI setup?

[Stublerone]

Originally Posted by flyingblind

The OP dose have a point. I have a mid-range card with 1GB memory and at least wish I had got a 2GB version. The best option for me would be to buy a second matching card if only I could be sure that would work properly. Do I waste the first card and go for a better single GPU or do I risk wasting more, albeit a smaller amount of money on a SLI setup?

Take into consideration, that 2 x1gb cards won't help. It is not 2 gb!!!!! It is still 1gb in sli, so your memory is way to low. Even a 2gb card will have problems in maxed setting and 1080p resolution, as the game will consume more than 2gb. My hd7970 is consuming up to 2,7 gb !!!! So even a sli with 2 x 2gb cannot help that much. So, 2 gb is the lowest memory, u should have to run it with some higher details, but still with stutters, if you are unlucky.

[Blackdog_kt]

Originally Posted by flyingblind

The OP dose have a point. I have a mid-range card with 1GB memory and at least wish I had got a 2GB version. The best option for me would be to buy a second matching card if only I could be sure that would work properly. Do I waste the first card and go for a better single GPU or do I risk wasting more, albeit a smaller amount of money on a SLI setup?

Sorry to be the bearer of bad news, but SLI doesn't increase your available video RAM.

I'm not exactly sure why, but i think that if cards use split frame rendering they render half of each frame, but they need to store the entire frame in each card's memory.

When they render alternate frames (eg, card 1 renders frame 250 and card 2 renders frame 251) the same holds, because each card has its RAM filled with an entire frame.

You do have double the video RAM but you also use double, so there is no gain in available memory.

[6BL Bird-Dog]

From experiance I got various results with different card combo`s single and X-Fire.
1x AMD Saphire Toxic 5870 Oc, poor frame rates and micro studders,had to use medium settings .
2x AMD Saphire Toxic 5870 Oc,best ever performance when the early patch release enabled X-Fire,Max settings, good high frame rates and only the microstudders low.Ruined when a small patch was bought out within hours because of graphics anomolys with Nvidia systems.
1xXFX HD 7970 Black Edition,Improvement on single 5870, but running at Very High in game settings made little difference ,frame rates improved slightly.
2xXFX HD 7970 Black Edition,with both last Alpa and Beta patches more or less the same as a single XFX HD 7970 Black Edition performance slightly improved at highest settings.
I tested the same cards and setups on the rig in my sig and did compare performance with RoF and iL2 1946 ,the latter of which does not have X-Fire support.
In Rise of Flight as I Improved my Gpu hardware I was able to increases my quality settings with also an increase in FPS .The 2x AMD Saphire Toxic 5870 Oc performance was slghtly slower than a single XFX HD 7970 Black Edition.
2xXFX HD 7970 Black Edition runs fluidly with all settings at max with the exception of AntAliasing which Inever run above 2x as it murders the fps in ROF.
iL2 1946 ran maxed out on all combinations ,seamlessly on 2xXFX HD 7970 Black Edition, with the Average FPS limited to 60mhz(my native screen res),but max frames are almost always over 1000fps.
The Clod dev team hit the sweet spot once for me on X-fire but have never unfortunately got close since.
In Cliffs of Dover`s present state apart from increasing in game video quality settings performance wise X-Fire is not functioning in anyway near to the Early X-Fire patch release which on my system was awesome compared to any patches before or after,the textures looked much better then too if a little bit too bright.

[SKUD]

Originally Posted by Blackdog_kt

Sorry to be the bearer of bad news, but SLI doesn't increase your available video RAM.

I'm not exactly sure why, but i think that if cards use split frame rendering they render half of each frame, but they need to store the entire frame in each card's memory.

When they render alternate frames (eg, card 1 renders frame 250 and card 2 renders frame 251) the same holds, because each card has its RAM filled with an entire frame.

You do have double the video RAM but you also use double, so there is no gain in available memory.

So let me make sure I have this straight. Nvidia wasted $$ putting an extra 1.5 GB of DDR5 on my 590 in full knowledge that it would never be used ?? Now they did it again with the 690 throwing away 2GB of VRAM because SLI can never use the VRAM from both cards. Those silly guys. Thanks for the tip.

[Blackdog_kt]

Originally Posted by SKUD

So let me make sure I have this straight. Nvidia wasted $$ putting an extra 1.5 GB of DDR5 on my 590 in full knowledge that it would never be used ?? Now they did it again with the 690 throwing away 2GB of VRAM because SLI can never use the VRAM from both cards. Those silly guys. Thanks for the tip.

Well, google is your friend.

EVGA forums, scroll down to 9th reply by user HeavyHemi: http://www.evga.com/forums/tm.aspx?m=1421266&mpage=1
Also note that the prevailing advice in that thread if you want to really crank up the resolution while also keeping the detail settings high, is to get a single card with the highest amount of RAM you can afford. So it's not only modern flight sims that work this way (RoF also had a lot of problems with SLI early on, but i can't comment on its current state because i don't have it on my PC), it seems to be a more widespread trend in other games too.

Tom's Hardware SLI and Crossfire FAQs:
http://www.tomshardware.co.uk/forum/...crossfire-faqs

Incidentally, in the above link you can also find this little gem:

Do SLI or CrossFire always improve performance ?
Not always.
There are some games that don't benefit from MultiGPU technology(or require a patch in order to utilize it).
For example,Flight simulator X doesn't benefit from either SLI or CrossFire.
Another example is StarCraft2 which barely benefits from more than 1 card

So FSX, a flight sim that was very demanding in graphics and CPU until hardware could could catch up with it, doesn't benefit from it. Sounds very familiar. Also note that Starcraft2 is a blockbuster AAA title.

Both of them are made by companies that could throw tons of cash on the issue. FSX is getting old and microsoft is more concerned with selling DLCs for its new MS Flight, but this wasn't always the case. Yet, they didn't fix it.
Also, SC2 is at its peak and its only part one of a trilogy, with a highly competitive multiplayer scene (think professional gamers who get paid like footbal players to take part in tournaments, etc) and the company behind it (Blizzard) has the enormous world of warcraft MMO cash-cow at its disposal and raving mad fans who buy everything they release (eg, the recent Diablo III).

If these guys can't do it or won't spend the time and money to, then the only reason i can think of is that SLI/Xfire setups are a bit too particular in terms of how you code your game in order to work correctly. It seems like the game has to be written around it and since it's a somewhat rigid and not so evolving technology (the cards evolve, but the technologies that pair them not so much), maybe it's not worth the compromises in other parts of the engine?

I'm just thinking out loud here, but the whole thing seems to completely debunk the entire "two cards = double the performance" logic. I've been ordering my PC components separately since forever and the only people i routinely see going for SLI setups are those that primarily focus on action/shooter games (simpler engines, small maps, elementary game mechanics, so all the PC has to do really is to run good graphics at a high frame rate).

The bottom line is, just because we might have some extra money to burn on a PC build doesn't mean we should go for the most expensive options. They might be kind of specialised in what they work well with.