XFIRE and 3990X & multiple GPU’s

LFell

n00b
Joined
Mar 19, 2021
Messages
5
Hello, new to the discussion & forum, Hello everyone.
Question, will a AMD Thread-ripper 3990x be able to accept 2 gpu‘s from a motherboard of: ASUS ROG Radeon RX Vega 64 STRIX- commonly paired on Amazon with thermal take memory of 4,600 MHZ and 2 Gpu’s listed as RXVEGA64-O8G-GAMING 8GB 2048-Bit OC, however when I search on Amazon ... with or without a crossfire bridge. I don’t see the crossfire bridge connector on the new cards in the pictures. When I list crossfire in the search it returns the Asus Rog board and the Asus gpu But I don’t see the crossfire bridge in the image.

What I want: AMD Ryzen Threadripper 3990X 64-Core 2.9 GHz Socket sTRX4 280W 100-100000163WOF Desktop Processor.
and also: Sapphire 2x (2) 11308-01-20G Nitro+ AMD Radeon RX 6900 XT PCIe 4.0 Gaming Graphics Card with 16GB GDDR6

so..

Do the new boards/processors require xfire to do their Job When using 2x the new generation GPU’s ? I have been using 2x 7890’s I990x processor, Dual X Radeon sapphire cards in crossfire mode but my rig has reached the 8 year mark and I would like to upgrade And I have been using crossfire for the last few years (8) and it seems to provide a significant performance boost. I am a computer programmer and I am always pushed to improve. i work from home and the place I work for will pay most of the price for whatever I need. And I also have 2 new 2560x1600 30 inch inch displays. And a ROG gammers addition Mob III With 4 x 2terabyte, 7200 rpm drives and 2100 MHZ memory.

Thank you for you comments And suggestion.

Larry
 

GoldenTiger

Fully [H]
Joined
Dec 2, 2004
Messages
22,141
No, newer cards don't need a bridge but Crossfire is a dead tech now. Games won't benefit and I'm not sure if the newest cards even support it. I know nvidia ones no longer support sli.
 

LFell

n00b
Joined
Mar 19, 2021
Messages
5
No, newer cards don't need a bridge but Crossfire is a dead tech now. Games won't benefit and I'm not sure if the newest cards even support it. I know nvidia ones no longer support sli.
So I can just get the 2 new cards and they will not be used by the CPU without the crossfire bridge? And the cards will be used by the cpu?
 

mda

2[H]4U
Joined
Mar 23, 2011
Messages
2,105
For work -- the bridge, and crossfire/SLI is useless I think.

You can try removing the bridge on your existing setup and I don't think you'll notice a difference.

Having 2 cards in your system is likely sufficient for your workload - not necessarily needed in crossfire..

The only real benefit of actual crossfire and SLI are in games.
 

noko

Supreme [H]ardness
Joined
Apr 14, 2010
Messages
6,545
Hello, new to the discussion & forum, Hello everyone.
Question, will a AMD Thread-ripper 3990x be able to accept 2 gpu‘s from a motherboard of: ASUS ROG Radeon RX Vega 64 STRIX- commonly paired on Amazon with thermal take memory of 4,600 MHZ and 2 Gpu’s listed as RXVEGA64-O8G-GAMING 8GB 2048-Bit OC, however when I search on Amazon ... with or without a crossfire bridge. I don’t see the crossfire bridge connector on the new cards in the pictures. When I list crossfire in the search it returns the Asus Rog board and the Asus gpu But I don’t see the crossfire bridge in the image.

What I want: AMD Ryzen Threadripper 3990X 64-Core 2.9 GHz Socket sTRX4 280W 100-100000163WOF Desktop Processor.
and also: Sapphire 2x (2) 11308-01-20G Nitro+ AMD Radeon RX 6900 XT PCIe 4.0 Gaming Graphics Card with 16GB GDDR6

so..

Do the new boards/processors require xfire to do their Job When using 2x the new generation GPU’s ? I have been using 2x 7890’s I990x processor, Dual X Radeon sapphire cards in crossfire mode but my rig has reached the 8 year mark and I would like to upgrade And I have been using crossfire for the last few years (8) and it seems to provide a significant performance boost. I am a computer programmer and I am always pushed to improve. i work from home and the place I work for will pay most of the price for whatever I need. And I also have 2 new 2560x1600 30 inch inch displays. And a ROG gammers addition Mob III With 4 x 2terabyte, 7200 rpm drives and 2100 MHZ memory.

Thank you for you comments And suggestion.

Larry
The bridge for AMD cards have been gone for awhile, believe it was the HD 7000 series got rid of it and just used the PCIe bus. AMD has hardware support built into the GPU to speed up this communication path. Programs that use GPU compute normally will see 2 or more cards and use them as in like 3d rendering. Interesting was at the time AMD got rid of the Bridge, it have better scaling for the most part over Nvidia SLI using a bridge (tidbit).

DX 12 games can use more than one GPU if coded for it, Rise Of The Tomb Raider and Shadow Of The Tomb Raider can use both cards for example and scale exceptionally well.
 

LFell

n00b
Joined
Mar 19, 2021
Messages
5
For work -- the bridge, and crossfire/SLI is useless I think.

You can try removing the bridge on your existing setup and I don't think you'll notice a difference.

Having 2 cards in your system is likely sufficient for your workload - not necessarily needed in crossfire..

The only real benefit of actual crossfire and SLI are in games.
Thank you
 

mda

2[H]4U
Joined
Mar 23, 2011
Messages
2,105
Thank you
As I have 0 experience with your workload or recent crossfire setups, my guess is easily verifiable by removing the crossfire bridge.

If your application runs normally and as fast as it should, then we can confirm that crossfire indeed has nothing to do with the speed
 

Andrew_Carr

2[H]4U
Joined
Feb 26, 2005
Messages
2,270
Any hints on what specifically you're trying to run? I have a 6900XT and 5700XT in my computer and they both work together fine. I haven't tried it for gaming, but I can mine 100% on the 5700XT while gaming on the 6900XT and it works fine. Mining on both also works as expected.
 

The Cobra

2[H]4U
Joined
Jun 19, 2003
Messages
2,902
MGPU works fine in DX12 if it is setup in the game engine. DX11 Crossfire is no longer supported on the new 6X00 series. Vega was the last to truly support Crossfire, although when I had my Vega Frontier Edition cards in Crossfire, every driver update seemed to limit crossfire even more. MGPU in BF1 was horrible in MGPU mode. SLI is still only supported on the 3090, 2080ti and 2080 and the older cards high end Nvidia cards and still work on older games that have support for it. But since Microsoft setup DX12 at the dev level for multiple GPUs, it gave the GPU makers the excuse to no longer support it at the driver level.

That is not to say that there aren't games that don't support it, but they are few. As a multi-gpu enthusiast, it no longer makes sense to have multiple cards for gaming as long as the devs don't support it IMHO. I would love to have two 6900 XTs on my pc for gaming.
 

doubletake

Gawd
Joined
Apr 27, 2013
Messages
776
Just as a sidenote: Bridge connectors for AMD cards haven't been a thing since the R9 290 came around. Everything since then ran xfire communication through PCIe, so that's why you don't see connectors on cards after Hawaii landed (excluding rebrands like the R9 280x, which was still Tahiti).
 
Top