Hey @init_27, any luck getting your system to work? Pytorch 1.7 was just released, wondering if it properly supports 3090 cards.
Waiting eagerly to hear back on the results.
A6000 available for preorders. See the price. Not an option for me.
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A6000 seems to be around the same price as current RTX 6000? Very surprising, considering it has double the vram. Wonder when they’ll release a 24GB Axxxx version.
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I’m looking at a 2x rtx 3090 build but am concerned about thermals. I thought about water cooling but a custom cooling loop for 2 gpus was about 800 - 1000 euros extra and I run the machine remotely without being there if something fails with the water cooling.
Does anyone know if having 2 rtx 3090 in some AM4 motherboard does even fit (and if temperatures are okay?)
Well… You could you for a 2nd gen Threadripper or an Intel i9 HEDT processor and you’ll find motherboards that will easily support 2x 3090s, with one slot gap between the 2 cards.
Example of suitable setups: AMD 2920x + ASRock Taichi x399 or Intel i9-9920x + Msi MEG X299 Creation.
You could also search/wait for the gigabyte turbo 2 slot cards or the MSI hydro copper cards that come with water blocks.
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It depends. The question is a tad too generic.
I’d consider just two kinds of 3090: the FE, which requires 4+4 slots (card, card, card, empty, card, card, card, empty), or the Gigabyte Turbo.
You can fit two Gb Turbo in any decent motherboard, but for two FEs you need a classic workstation mb. If you want to go with amd, use a TR with this motherboard: https://www.asrockrack.com/general/productdetail.asp?Model=TRX40D8-2N2T#Specifications.
If you wan to go with Intel, you have plenty of options.
Two Gb Turbo are much more practical but loud. Two FEs are quiet, but you’ll need the correct mb layout. Do not underestimate noise output. Use the turbos just if you want to go with AM4 no matter what.
Of course there are always liquid cooled options, as the user above told you, but I somewhat dislike them. Just a personal opinion.
If you are investing in a machine you want to use for some years, I’d stay away from TR 2000, since they are far behind Xeons and TR 3000 both in terms of pure performance and power efficiency (perf per watt). Take it just if you find real bargain prices.
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Is there any news about when the 3090 will be back in stock on the major e-commerce website? I have my eyes on the ASUS RTX 3090 TUF. It seems to have pretty good thermals.
I can tell you where to find the following:
Inno3D GeForce® RTX 3090
MSI GeForce RTX 3090 VENTUS 3X OC
Zotac GeForce RTX 3090 Trinity
Street price ~1500eur + VAT (which is too high).
Send me a PM if you are interested. But I don’t like any of them. The only 3090 I like are the FE and the Gigabyte Turbo, for obvious reasons. Both impossible to purchase as of now.
I think you’re right @balnazzar, the Gygabyte looks very interesting. I might actually go for that one instead. Let me know if you’re able to find it at a normal price.
By the way, Puget run a test undervolting the 3090 and was able to obtain 95% of the performances at 280W.
I remember you mentioned this very same idea in this thread a few weeks ago. Might be ideal for running 2 or more 3090 without compromising temperatures inside the case.
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I’m pressing the people above really hard, but as of today they are still unable to find one at humane prices. It’s for sale at amazon.it for 2499. No way.
Typical. It works with any silicon. I run my four 2060 Super at 125W and they still deliver some 90% of their perf. The same stands for a Threadripper I acquired recently as my windows general purpose machine. People all over the internet complain that they are unable to cool their TR with 360mm AIOs, let alone air coolers. Still: https://ernststavroblofeld.medium.com/how-to-run-your-threadripper-3000-cool-quiet-for-a-change-e4d3c2169bf3
I think that if your target is just two cards, you will be better served with two FEs, provided that your motherboard allows for [card,card,card, empty, card card,card].
The FEs are extremely silent (while staying cool) even when your run them at 350W. Imagine at 280W.
The problem is that they are impossible to find. Or you have to buy them on ebay, with broken seals and minimum prices ~1800eur.
Another factor to take into account is that the RX6800 are out, all of them with 16gb, even the non-XT. So I think that a 3080 with 20Gb is becoming probable. If so, its cost/perf ratio would be even better than 3090’s.
Two cards for less than 2000 bucks and 40gb VRAM. That’s really something.
For those of you considering a Threadripper, the concerns I expressed previously were mainly about power requirements and the absence of professional motherboards.
A couple of weeks ago, however, I had the opportunity of building a TR system for a client of mine, and it seems that both of the above issues can be overcome quite easily.
I blogged about that build: https://medium.com/swlh/how-to-run-your-threadripper-3000-cool-quiet-for-a-change-e4d3c2169bf3
The bottom line is that even if you run it at almost half of its nominal TDP, it totally destroys everything Intel can put on the field as of today (and that won’t change with Cooper Lake, which is a further 14nm development).
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Asus just launched their own version of blower-style RTX 3090.
Would be interesting to see how the two (Gigabyte and Asus) compare in terms of temps under load.
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OT: I’m having troubles setting the Coolbits on 20.04. xorg.conf is not there anymore (of course) and the files in /usr/share/X11/ don’t seem to have any effect.
Suggestions? 
please this! 
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I agree, now that it is becoming more and more clear that the RTX 3080Ti should be launched this year with 20Gb of VRAM, I think 2 x 3080Ti are a better investment — assuming a price around $1000 each. Distributed training is becoming easier too, which makes this a no-brainer assuming you can’t afford a 2 x 3090 build.
It is not clear to me though if we need a super recent CPU to avoid bottlenecks when feeding 2 x 3080Ti. My current system is based on an Intel Core i7-8700K 3.7 GHz 6-Core Processor. So far it has served me well. Do you think I’ll have to upgrade to AMD Threadripper? Nvidia is pushing to move preprocessing to the GPU although this is not mainstream yet.
That’s not easy to assess, and it’s quite dependent upon what you are actually doing. Having a capable CPU won’t hurt, that’s for sure.
Apart from preprocessing loads GPUs won’t (yet) handle, one has to consider lanes (2x3080s on gen3 x8 can be a bit sacrificed, and what if you want to add a third card?), fast gen4 storage, etc…
Assuming that you got your 8700k on a Zx90 motherboard, I’m not even sure it can provide two gen3 x8 slots.
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Thank you for your answer @balnazzar.
I’m no expert when it comes to hardware so pardon me if I say something stupid.
I have an Asus ROG STRIX z370e. Looking at the motherboard specs (link), it says it has:
- 2 x PCIe 3.0 x 16 SafeSlots (Support x16, x8/x8)
- 1 x PCIe 3.0 x 16 (at x4 mode)
- 4 x PCIe 3.0 x 1
The CPU offers 16 PCI lanes. Quoting something I found in another forum:
As has been pointed out, the CPU has its own PCIe lanes then the Chipset has its own lanes.
The 8700k has 16 PCIe GEN 3.0 lanes and an additional 24 lanes on the chipset for I/O, M.2 PCIe slots aside from main 2 ones.
Now with the z370 board, the CPU lanes are normally dedicated to the primary x16 slots with the additional slots wired to the chipset lanes
Wouldn’t this mean that, assuming there is enough space between the 2nd and 4th slot (those that have x16 lanes) I should be able to run two GPUs on gen3 x16 — one using the PCIe lanes from the CPU and the second from the chipset?
I took a look to the manual, and unfortunately it lacks a proper schematics (as it is customary with ‘gaming’ boards). So we cannot really say what’s connected to what.
All we can assess, since the manual says it clearly, is that if you populate both x16 slots, they will drop to x8/x8 gen3. There is no way around that.
Note also that chipset lanes are employed for many different tasks, since network chips, usb, m.2, sata, etc… They all eat up chipset lanes, directly or indirectly.
AFAIK, no “desktop” motherboard can provide more than x8/x8 gen3 (Intel)* or x8/x8 gen4 (AMD)**, and they are egineered that way precisely because Intel and AMD want you to buy prosumer or professional hardware for any serious multi-gpu usage scenario.
(*) with the notable exception of some boards equipped with PEX 8747 pcie switches, see for example the Supermicro C9Z490 series.
(**) A common misconception: a lot of people bought the Asus WS x570 ACE since it can provide x8/x8/x8 gen4, but the third electrical x8 slot is choked by a link to the CPU with only 4 lanes.
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Gotcha! Is the difference in performance between gen3 and gen4 in deep learning tasks similar to what seen in gaming benchmarks? In most benchmarks the difference seems negligible (link).
Similarly, it seems not always the case that 16x/16x is faster than 8x/8x (link).
I’m asking just out of genuine curiosity. I’m sure that gen4 16x/16x is faster than gen3 8x/8x, but I wonder by how much? I’ll keep that in mind next time I’m going to upgrade my system.