R9 290X and 290 Blog: modernizing multi-GPU gaming with XDMA

[Diagro]

Crikey! So now with cross fire running from the same bus 3 & 4 card setups would surely get insta choked on 2.0? As the bus already appears to be at its maximum throughput using an external bridge, the data between cards being sent through the lanes would now also become congested?

Maybe, But don't forget AMD said that the external connections were already being used to the max hence why they had to change it.

I'm sure AMD has thought of all these issues

 

[andybird123]

According to AMD's Blog. The tech is supported on PCI-E 3 8X (for xfire) and PCI-E 2 8X setups.

There is plenty of bandwidth left over

did you look at the link I posted?

if pcie 2.0 is being saturated by 4x680 at high resolutions (the only time you would really want or need a 3-4 card setup) then you can be absolutely certain that a 3 card 290/x setup would be bottlenecked at the same resolution on pcie2.0

there can't be "plenty of bandwidth left over" in that situation

hopefully it is a moot point, as someone with enough cash to splurge on super high res monitors and multiple graphics cards should easily be able to get a mobo and CPU to suit, but it is worth being aware of for people with perhaps a 2600k considering a move to 4K

a 40% improvement in frame rate from ONLY changing pcie2.0 to 3.0 is a very clear indication that bandwidth was a major issue at 2.0, removing an extra 900mb/s would only make that worse (1800mb/s as the cards have 2 connectors each?)

 

[Dicehunter]

Yes I did try it..... Made no difference at all.

So I went to Nividia for the first time and they've made you guys look silly with how effortless the hardware and software installation was.

Nice baiting
I've recently installed a 290, A 290X and a 780 Ti, There was literally no difference between any of the during installation, Put card in, Boot up system, Install drivers, Reboot, Done.
How is installing an Nvidia card effortless compared to an AMD card ?

 

[LtMatt]

I've recently installed a 290, A 290X and a 780 Ti, There was literally no difference between any of the during installation, Put card in, Boot up system, Install drivers, Reboot, Done.

Welcome to the darkside Dice.

Did you buy it (290+290X) for Mining or gaming or a bit of both?

 

[pgi947]

did you look at the link I posted?

if pcie 2.0 is being saturated by 4x680 at high resolutions (the only time you would really want or need a 3-4 card setup) then you can be absolutely certain that a 3 card 290/x setup would be bottlenecked at the same resolution on pcie2.0

there can't be "plenty of bandwidth left over" in that situation

hopefully it is a moot point, as someone with enough cash to splurge on super high res monitors and multiple graphics cards should easily be able to get a mobo and CPU to suit, but it is worth being aware of for people with perhaps a 2600k considering a move to 4K

a 40% improvement in frame rate from ONLY changing pcie2.0 to 3.0 is a very clear indication that bandwidth was a major issue at 2.0, removing an extra 900mb/s would only make that worse (1800mb/s as the cards have 2 connectors each?)

This is pretty much the point/question I was trying to ask

Once saturated what would take the perf hit, bandwidth to the cards or to crossfire communication?

 

[andybird123]

yep, good question, end result would be the same, reduced FPS due to a bottleneck, I guess if crossfire always prioritised itself then it would just be the bandwidth causing the issue, if it didn't then you could get a situation where like VRAM running out you got dips to basically 0 FPS, so crossfire being the priority would seem to be the best case

^^ pure guesswork, would need testing 3-4 cards at 7680x1440 or 4K on pcie2.0 to confirm

 

[Dicehunter]

Welcome to the darkside Dice.

Did you buy it (290+290X) for Mining or gaming or a bit of both?

Well I installed the 290 and 290X for 2 of my work colleagues as they have just been initiated into the PC Master Race Club

I myself run a 780 Ti SLI setup but honestly I saw no difference in the difficulty of the installation process of all 3 cards, Nowadays you could do it with a blindfold on, Even installing drivers for all 3 was identical apart from the AMD/Nvidia branded screens

 

[GoogalyMoogaly]

I will say, on a number of occasions with both my 7950 and 290 setups the recent 9.4 and 9.5 betas failed to install as a clean install (they would install over a previous install).
I don't remember ever having that issue with Nvidia drivers and to be honest I've used a lot more Nvidia cards and drivers than AMD.

 

[LtMatt]

I will say, on a number of occasions with both my 7950 and 290 setups the recent 9.4 and 9.5 betas failed to install as a clean install (they would install over a previous install).
I don't remember ever having that issue with Nvidia drivers and to be honest I've used a lot more Nvidia cards and drivers than AMD.

Have you tried that DDU tool everyone keeps going on about? Are you on W8?

 

[GoogalyMoogaly]

Have you tried that DDU tool everyone keeps going on about? Are you on W8?

Win7 and I was using the DDU thing at the time, repeatedly (must've tried 10 times or more).

 

[LtMatt]

Win7 and I was using the DDU thing at the time, repeatedly (must've tried 10 times or more).

I've had the drivers fail to install like you, but this has only occured after a part failed install. Rather than uninstalling first via CCC/add remove progs i used a driver sweeper tool and this seemed to mess it up. Must be a missing reg entry somewhere or something. I never could get to the bottom of it so just reformatted at the time. You may or may not have done this, but if a install goes wrong or does not fully install. Uninstall everything the proper way, restart then use the driver sweeper tools. This could just be an instance that affected me and driver fusion though, not sure. Either way ive not had problems since with *ANY* drivers.

Did 13.12 WHQL install ok? I know the beta's have an unsigned driver (the frame pacing part) and this did get flagged up by windows certificate protection a lot. Stopped part of the driver installing on occasion. That problem will not occur with WHQL.

 

[GoogalyMoogaly]

Did 13.12 WHQL install ok? I know the beta's have an unsigned driver (the frame pacing part) and this did get flagged up by windows certificate protection a lot. Stopped part of the driver installing on occasion. That problem will not occur with WHQL.

I couldn't be bothered going through all the hassle again, so just installed them over the top of the 9.5 betas (that were installed on top of something else).