Build with two Nvidia RTX 3090

[slyexe]

Someone mentioned to me that there are thermal restrictions on the 3090's and I wouldn't be able to use more than one of them.  Slyxe I see you were using two RTX 3090's.  Could you give me some insight as to what your build looks like?

Thermals are more an issue in the cryptomining scene. Mining ETH or other coins is hard on the memory chips of GDDR6X which would be the issue I would suspect you're talking about. As for my cards they are under 2 months old and I believe the manufacturers have addressed the issues with the thermal pads on the memory. My cards memory chips usually hit 85-95ºC which is "safe" in my opinion as the memory temperature threshold is set to 110ºC. However, mining and cracking are 2 completely different topics and also totally different aspects of how a video card can be used. I usually have some 120mm fans plugged into the fan expansion slot on the video cards to put on the backplates to cool the memory but had recently given them away and haven't had any issues.

If you're thinking of expanding, beyond 2 cards, I myself do not have much experience in that aspect. However, I would say a server motherboard would offer the best features for such case. I think one of the hashcat developers had a company that handle specially designed rigs - Google Sagitta HPC  for more info.

Here is what the rig I have looks like, it's nothing special.