Generic Multiple GPU discusssion

Tom M
Tom M
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As part of a decluttering

As part of a decluttering process (not yet fully done) I ran across a 8x to 16x pcie adapter you could use for an 8x without an open slot in the back.

This makes it possible to install a 3rd GPU on a motherboard even if there is wiring in the way.

I think it may now be possible to install 3 gpus "on the motherboard" of my 3950x box.

Have to find a longer screw to connect the back plane though.

And that would leave my Epyc system with as little as two rx 5700 gpus. :)

The only strong reason to go this route would be because I wanted to slim down to one Boinc machine.

Tom M

 

Over the hill?  What hill?  I don't REMEMBER any hill...
A Proud member of the O.F.A. (I've forgotten what that stands for.... ;)

 

 

 

 

Exard3k
Exard3k
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Hey guys I need some

Hey guys I need some advice....I'm going to buy a new GPU (actually full PC) in the next months. And I'm checking my options, as there are several things to consider. Linux, Gaming, VFIO/IOMMU Passthrough and numbercrunching in E@H.

 

It really comes down to 6800XT or 3070/80 (non-Ti). And as we are in the E@H forums, how do these two compare for usual workloads? I got a 2060 but I need a second GPU for VMs and dual GPUs is also beneficial to E@H.

Keith Myers
Keith Myers
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Probably easier to deal with

Probably easier to deal with just one set of video drivers so getting another Nvidia card is probably the best.

And with the new GRP application, the Nvidia cards are just as fast as the AMD cards.

 

Exard3k
Exard3k
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Keith Myers wrote:Probably

Keith Myers wrote:

Probably easier to deal with just one set of video drivers so getting another Nvidia card is probably the best.

And with the new GRP application, the Nvidia cards are just as fast as the AMD cards.

 

Thank you! Exactly what I was looking for....I'm fairly new after some decade of nonparticipating in a any project. I figured as much on the driver side, but didn't know about the quality differences between applications regarding AMD/NVidia. I'm just happy I got everything running now. Good some vets can share their knowledge. Just waiting for the new Threadrippers to get a (long overdue) upgrade on my very old Haswell-CPU system.

Ian&Steve C.
Ian&Steve C.
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Tom M wrote: As part of a

Tom M wrote:

As part of a decluttering process (not yet fully done) I ran across a 8x to 16x pcie adapter you could use for an 8x without an open slot in the back.

This makes it possible to install a 3rd GPU on a motherboard even if there is wiring in the way.

I think it may now be possible to install 3 gpus "on the motherboard" of my 3950x box.

Have to find a longer screw to connect the back plane though.

And that would leave my Epyc system with as little as two rx 5700 gpus. :)

The only strong reason to go this route would be because I wanted to slim down to one Boinc machine.

Tom M

 

if you want to declutter and move down to 1 monolithic system, why not move everything to the system that can best handle multi GPU? The Epyc. Seems the most logical choice to me. 

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Keith Myers
Keith Myers
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Well for example this

Well for example this host host/12291110 is using a RTX 3080 and 2080 for FGRPB1G Gamma-Ray Pulsar tasks.

RTX 3080 130 seconds

RTX 2080 250 seconds

 The GW app is not as fast but both cards are capable of running the GW work in around 7-10 minutes.

 

Tom M
Tom M
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At current inflated prices

At current inflated prices (both NVIDIA and AMD) what card would you buy for a two or three card system?

Try to ignore "sunk costs".

Today the...

The used Radeon VII's seems to be going for $1800~ up.

The Rx 6900 xt seems to be going for $1600 up

The Rx 6800 seems to be going for $1200 up.

The Rx 5700 xt seems to be going for $800~

The Rtx 3080 seems to be going for $1300 up.

The Rx 3080 ti seems to be going for $1700 up.

The Gtx 1080 seems to be going for $500~

Tom M

 

Over the hill?  What hill?  I don't REMEMBER any hill...
A Proud member of the O.F.A. (I've forgotten what that stands for.... ;)

 

 

 

 

Ian&Steve C.
Ian&Steve C.
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with some patience and luck,

with some patience and luck, you can get the RTX 30-series cards for closer to "normal" price. don't shop for these on ebay. you will overpay.

I got my 3080Ti for $1500, and that was a higher end overclocked and watercooled model (still overpriced).

watch the newegg shuffle and try to get a card from there. you'll overpay a little and maybe have to pickup a motherboard or PSU, but you wont have to pay a scalper on ebay. I usually recommend the EVGA queue system also, as that's not I've score most of my 30-series cards, but you can realy only succeed there if you signup for new product releases, and I don't think they'll have any more for a while and the lists are already super long.

30-series will probably be the best bang for buck. even if you paid $1700 for a 3080Ti, it outperforms that $1800 Radeon VII by about 25%, has better power efficiency, better driver support, and overall less headache.

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