Daz Studio won't detect three RTX 3090 cards?
chrislb
Posts: 100
If I put one or two RTX 3090 cards in the system Daz detects them and it works properly according to the logs. If I put three RTX 3090 cards in the system Daz don't detect the third card. However Windows and other programs do.
I can put three GTX 1070 cards in the system and Daz detects them and uses all three.
I can put the two RTX 3090 cards and one RTX 2080 Super or two RTX 2080 super cards in the system and Daz detects and uses all 3 or 4 of them.
I'm using a 1300 watt power supply and two 850 watt power supplies to power the PC and the three RTX 3090 cards. Running two RTX 3090's and two RTX 2080 supers uses mroe power than three RTX 3090 cards, so I don't think its a power issue..
I don't have a lot of time to troubleshoot this, but I was wondering if its an issue with the RTX 3000 series cards and Daz?
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Comments
Can you describe your full system setup? I don't understand how you can have 3 power supplies in one system. Isn't the "power on" signal for a PSU comes from the 24-pin motherboard connector? How do you power on all 3 PSUs at the same time?
You can buy dual psu adapters for 2-way, or something like add2psu for more than two.
From my experience with a 4 x 2080ti setup, for many reasons I would instead spread the GPUs over multiple systems. The farther off the beaten track you go, and this is a pretty exotic solution, you are more and more likely to become the trailblazer who performs the public service of finding all the corner cases that should work but don't, the vendors never tested and don't want to help you because it is easier to blame another component in your system made by someone else.
Besides, think of how awesome a 2 x 2 x 3090 setup would be... as soon as the MSRPs are real, that's what I'm going to do.
I found this:
24-Pin 20+4Pin Triple PSU ATX Power Supply Adapter Cable 18AWG Wire For Mining
https://www.newegg.com/black-tekit-1-5-cable-connectors/p/1W7-000K-00009
Instead of using a relay, I think it just wires all the "power on" signals together.
With add2psu daisy-chaining, you would have to use two extra 4-pin molex connectors.
Total wattage:
1300 + 850*2 = 3000 watts / 120 = 25 amps
Is this setup connected to a 30 amp electrical outlet? Typical household outlets are only 15 amps.
It's like plugging 3 computers into one wall outlet, which is a very bad idea. And yeah, PSUs are never fully loaded, but the system still has the potential to draw that much anyway.
That's just another reason why cramming more GPUs into the same system is a bad idea in my opinion, which is an even worse idea with Ampere. With two systems, one can smooth out the power requirements over different circuits that even are physically spread out over the house.
At my house, I was tripping the 15A circuit, so without having to re-wire anything from the street, an electrician was able to give me two 20A circuits, both on different legs with a 30A capacity on each leg, in addition to the rest of the room on a third 20A circuit. During a test render though, he said it never drew so much as 12A. That's with 4 x 2080ti running E-Cycles, and so that lends credence to the idea that rendering is much easier on GPUs than games.
The other parts are:
AMD R9 3950X CPU
64 GB of DDR4 3600 MHz RAM
MSI x570 MEG ACE motherboard
EVGA 1300 Watt G2 power supply
Seasonic 850 Watt power supplies
2 NVME SSDs
SATA SSD
7200 RPM SATA hard drive
One GPU mounted in the case to the top PCIEx16 slot
PCIEx16 riser cables for the other 3090s
When I get the water cooling waterblocks I'll have the space to mount three 3090s in the case.
I verified all three power supplies were running and all 3 cards were detected by Windows and other software.
When I ran 4 or more graphics cards before, I was able to use PCIEx1 to X16 adapters for the 2080 Supers and they worked fine.
The case supports up to 3 power supplies, but the 1300 watt power supply and an 850 watt power supply will supply more than enough power for the CPU, 3 GPUs and other components. I limit each graphics card to 420 watts and that's a total of 1260 watts power draw. Since I don't use the CPU for rendering, I can limit its max power draw int he BIOS to under 200 watts. The max power draw of the system at the wall will be under 1600 watts.
The power supplies don't draw their maximum rated power unless its needed by the components. Therefore, a 30A circuit isn't needed for three power supplies.
Other rendering and video editing software detects and uses the three 3090s. Daz only sees two of them. I'm just wondering why Daz won't see three 3090s, but will see 4+ GPUs if I only use two 3090s.
Three 3090s in one system is about the limit of a 15A circuit with a little headroom for other components, a monitor, and a CFL or LED light for the room. The 3090's rarely will hit their peak power draw during renders and their maximum power draw can be limited by software such as MSI afterburner or EVGA PX1. Limiting two 3090s to under 400 watts each only increased render times by 1 or 2% at most for me.
Yes, I don't doubt what you're saying at all. But for me the problem was not necessarily my system, but rather the other things on the same circuit. I had no idea microwaves, vacuums, and even a laser printer drew so much current. A dedicated circuit is a must, or all the precise calculations one does are moot.
Actually, I also vote for the "use a second system". As an industrial control engineer, we often use dual DC supplies, but for redundancy, not 'splicing' amerage. The PROBLEM with a simple Y-cable is the power supply with the higher voltage (say 5.006v instead of 5.002v) supplies more current. They will never balance. So if you have 2 x 850-watt supplies, most likely 1 is max'ng out at 850w and the other chuckling as it supplies only 200w! Worse, the one which max's might start to fold-back power, and thus its voltage drops, so the 2 supplies oscillate between full output & much less. I can't see how that is good for a computer or expensive graphics display.
Specifically, for industrial usage, we pick power supplies which 'sense' each other and try to keep in balance - avoid this oscillation. No $5 cable will do this.
The only wire spliced here is the "power on" signal. This is to tell all PSUs to turn on/off at the same time. I don't know what people use to hook up a huge farm of cards, like 50 or more, but for 3 cards, this should work ok.
As others have said, the splitter cable only tells the other PSU to turn on or off. They don't feed power into the same components. The second PSU would be delivering power to differnet components than the first PSU.
I might not have time to troubleshoot the three 3090 issue again for a while unless someone wants me to build them another multi GPU RTX 3090 system in the near future.