Crossfire through chipset

[MAP_Finder]

I have a R9 Fury X I got used not long ago and although it works fine for the games I want to play, I'm worried that all the games coming out with the next consoles will be too much to play them at 60fps 1080p if I opt for high settings. My motherboard (TUF X570) supports Crossfire, but only through the chipset. I'm hoping that to upgrade I can add another used Fury X and go but I've heard that Crossfire through the chipset is in general a bad idea, I've run one GPU through a chipset before and it was fine. What are some of the issues I may encounter if I do crossfire through the chipset and are two R9 Fury X(s) a good idea for a GPU upgrade in the used market?

[mariushm]

It's not that it's a bad idea through chipset, but in general it's a bad idea to do crossfire because games have to actually support crossfire/sli to get a performance increase, and in lots of cases, you don't get double the performance... you'll get something like 60-80% more performance.

If the game doesn't support it, or isn't aware of it, the 2nd card will sit idle doing nothing.

By design, the cards also have to keep the stuff in memory synchronized, so your cards with 4 GB of memory will suddenly behave like 2 GB cards so games with lots of textures and crap may not work well, because of low VRAM.

 

I'd sell the fury and buy something more modern, don't bother with crossfire.

 

One other thing you have to keep in mind is that the slot connected to chipset is probabbly only pci-e x4 electrically, so you'll choke the first video card by making it wait until the 2nd card is done and sync-ing through the pci-e x4 and chipset.

[Windows7ge]

The only reason I know of why it's bad is bandwidth but GPUs generally don't need the full bandwidth that their slots are capable of. Usually running on a x8 slot is fine especially if the GPU & slot are gen 3 compatible.

 

As for running two in general I don't think it's worth it. If you can cut back on things like AA and rendering further distances your FPS should still go through the roof with just one card especially if you're only at 1080P.

[MAP_Finder]

1 minute ago, NZgamer said:

Crossfire/SLI is essentially dead now. Your best bet is to buy one good GPU. The new games coming out with the consoles should be optimised for PC.

I've heard that most new games either aren't supporting Crossfire/SLI or don't scale well with multi GPU setups, that may be the reason come to think of it.

[Moonzy]

7 minutes ago, MAP_Finder said:

I've heard that Crossfire through the chipset is in general a bad idea

no, you're wrong

 

Crossfire is in general a bad idea.

just use a single better GPU less hassle

[MAP_Finder]

8 minutes ago, mariushm said:

 by design, the cards also have to keep the stuff in memory synchronized, so your cards with 4 GB of memory will suddenly behave like 2 GB cards so games with lots of textures and crap may not work well, because of low VRAM.

Wow, I did not know that, right now the Fury is struggling with 4GB of VRAM, with 2GB per a card I'd imagine it would be a big problem.

[Senzelian]

As mentioned before, Crossfire is dead.
If anything you'd need two graphics cards supporting DX12 mGPU, but even then not all developers add support for it.

I'm not sure whether the Fury handles DX12 very well or not. I know it has support for it, but so did the GTX 900 series and that was not a great experience.

[MAP_Finder]

Just now, Senzelian said:

As mentioned before, Crossfire is dead.
If anything you'd need two graphics cards supporting DX12 mGPU, but even then not all developers add support for it.

I'm not sure whether the Fury handles DX12 very well or not. I know it has support for it, but so did the GTX 900 series and that was not a great experience.

I've had occasional crashes and stuttering with DX12, overall it isn't terrible but isn't great either.

[Senzelian]

2 minutes ago, MAP_Finder said:

I've had occasional crashes and stuttering with DX12, overall it isn't terrible but isn't great either.

Yeah, then I wouldn't recommend going that route either.

 

12 minutes ago, mariushm said:

By design, the cards also have to keep the stuff in memory synchronized, so your cards with 4 GB of memory will suddenly behave like 2 GB cards so games with lots of textures and crap may not work well, because of low VRAM.

That sounds to me like wrong information. Where did you get that from?

[Moonzy]

15 minutes ago, mariushm said:

By design, the cards also have to keep the stuff in memory synchronized, so your cards with 4 GB of memory will suddenly behave like 2 GB cards so games with lots of textures and crap may not work well, because of low VRAM.

afaik, the memory is duplicated between the cards

so

4+4GB = 4GB usable

[SpaceGhostC2C]

4 minutes ago, MAP_Finder said:

Wow, I did not know that, right now the Fury is struggling with 4GB of VRAM, with 2GB per a card I'd imagine it would be a big problem.

That is incorrect. 4GB cards will behave as 4GB cards. The mistake people make is thinking that, because each card has 4GB, then you'll have 8GB total VRAM: you won't, you'll just have 4GB duplicated. But there is no reduction from using crossfire.

 

As someone who actually has used crossfire, it's not as useless as it's made to be, but running the latest game is precisely the worst scenario for multi-GPU setups. It has always been, and it has only gotten worse as games and GPU makers move away from SLI/Crossfire. If we were discussing not-so-recent games, with dedicated crossfire or SLI profiles, it could be a different story, depending on how much you need to pay for the second card (and how much you pay for electricity ).

 

Having said all that, 1080p 60FPS doesn't seem too much to ask from a single Fury X...

[MAP_Finder]

Well, maybe I'll wait until Big Navi comes out and see what the games seem to need out of the GPU and buy a graphics card when it's time to upgrade. Maybe a used Vega 64 by then if they still hold up well, I used to have one but then it broke... It was good while it lasted

 

[mariushm]

Yeah, I may be wrong about that... or outdated.

There were several techniques of getting 2 or more cards to collaborate and share data, I imagine more modern methods don't need copies of the other card's vram data anymore.

 

Still, doesn't change the fact that Crossfire or SLI is overall not worth it.

[MAP_Finder]

2 minutes ago, mariushm said:

Yeah, I may be wrong about that... or outdated.

There were several techniques of getting 2 or more cards to collaborate and share data, I imagine more modern methods don't need copies of the other card's vram data anymore.

 

Still, doesn't change the fact that Crossfire or SLI is overall not worth it.

Yeah, especially seems that way by the fact that some new API could come out and dub both GPUs in the setup useless for any game that uses them, I'd imagine five year old cards like the Fury X aren't well optimized for feture APIs, or DX12 for the matter.

[MAP_Finder]

Does anyone know what is wrong with specifically Crossfire through the chipset though? I've watched AHOC and he says "Crossfire can do weird things through the chipset, it does work but it's unpleasant" does anyone know what he means by that? Other then the issues that occur with multi GPU setups in general like poor scaling.