P3D V5 with 2 videos cards

[Virtual Flight Realm 29]

Hi guys did any one test P3D V5 with two video cards ? With DX12, I guess P3D V5 can handle 2 videos cards and double vram 😉 Hope one of you can test this.

Edited May 16, 2020 by Virtual Flight Realm

[DWadsworth 13]

I run it with 2080TI to my main monitor with P3D and use the i9-9900ks video output to drive a second monitor with panels, programs, etc.  No problem.  Can't see why a second video card would not work.  Depends on how you want to layout screens and views.

[micstatic 4,319]

from what i read 2 11gb cards do not equal 22gb in P3D.  Not sure it helps.  I have a 1080ti.  I have a 43" tv as my Virtual Cockpit.  The use two 23" monitors for the side.  Also have a mcdu which is essentially a 4th monitor  made by skalarki.  Previously I thought it made sense to use the integrated graphics to ease the load on the 1080ti and power the others.  Then I discovered every now and then P3D would decide to start using the integrated graphics despite the tv being plugged into the 1080ti.  I read alot and tried to fix it.  Ultimately I plugged everything into the 1080ti and deactivated the integrated graphics.  The problem is gone and I don't see any less performance.  Just something to keep in mind.  

[JamesIL 16]

There is a post on the lockheed martin forums that its not implemented yet but eventually will be.

[Emile 28]

Hello, 

I use 2 video cards a 950 and a 1080 TI with 3 monitors on V5 HF , 

No problems

[Virtual Flight Realm 29]

15 hours ago, Emile said:

Hello, 

I use 2 video cards a 950 and a 1080 TI with 3 monitors on V5 HF , 

No problems

Thx Emile, what is your VRAM usage and diponibility in P3D V5 ? Did you notice a combination of vram with P3D V5 ?

15 hours ago, Rob_Ainscough said:

DX12 doesn't automatically mean two GPU can combine their VRAM ... it's technically possible with DX12 since there is more direct access to the GPU, but would need be coded by the developers to leverage that which is probably a high risk (read lots of breaking changes in terms of compatibility to existing products).

I no longer have multi-GPU computers as I found NVLink with Performance mode to not really provide much of a benefit in V4.5, however I have not tested in V5 ... maybe someone else can chime in?

You can certainly use multi-GPUs in P3D V5, no restrictions there, same as P3D V4.5.

I would highly recommend disabling any integrated graphics via BIOS, causes many issues.

Cheers, Rob.

Thx Rob, DX12 allows softwares to combine the power of several GPU, DX 12 compliants, including AMD and Nvidia video Card for instance. You're right the question is P3D V5 does and if yes does it increase vram & performances ?

Edited May 17, 2020 by Virtual Flight Realm

[Emile 28]

Hello, 

"Thx Emile, what is your VRAM usage and diponibility in P3D V5 ? Did you notice a combination of vram with P3D V5 ?"

To be honest I never checked the VRAM.....

[jabloomf1230 2,445]

Even if "stacked VRAM" worked in P3d5, the primary video card would still be accessing the secondary card's fast VRAM via a slower PCIe bus. If the PCIe 4.0 bus specification is supported, it might make more sense, but it would still be slower than accessing the primary card's VRAM. This is why you don't see any VRAM add-on PCIe cards for sale. 

There have been video cards with expandable VRAM slots but it's a tricky design to keep such a card cooled and supplied with the correct power.  And why would anyone sell such a card to consumers? The whole point of the video card market is planned obsolescence.

Edited May 17, 2020 by jabloomf1230