Can you share your budget or a range in what you would like to spend?
Also, are you wanting to use a card that Autodesk will support or are you happy to take that risk. Keeping in mind that the dev team has said there are good reasons to only use NVIDIA workstation cards and not gaming cards. I have used gaming cards on home systems before with no issues but not saying you might not stumble onto some.
Probably your best bet for that cash used would be a Turing RTX 5000. 2 generations old but newer than the Z840.
For that sort of money you might get a P6000 if you are savvy and definitely a P5000 if you go used, which is the generation of the last Z840s. The Turing is a newer card though so I’d choose that over the P series cards.
If you are happy to go a gaming card, a RTX3090 can be had for that money and is probably a better option then any of the 40series gaming cards at the price due to the VRAM. Be warned though, used gaming cards are often pushed hard so I would not trust the reliability of the thing. If it has been over locked and driven hard it could die fast.
I also think of burn as very use-case centric. As in, if
you have a big job
and it’s consistent business
and burn will actually help
and you can pay for the burn nodes with ONE job
→ then it’s worth it.
But burn is like any other kind of hardware or cap-ex purchase: it rots like fresh veggies. You gotta use it when it’s fresh and get new ones when it’s old and rotten and smells like garbage.
I’m not against it, it’s absolutely saved my ass on multiple occasions. But it should meet a few criteria before going down that road. There is NOTHING sadder than old computers in your office collecting dust.
If you have done older workstations sitting around, Burn is an excellent use for them. Done that a few times and have never had issues with them either. If it’s an older system that dies after a couple more years use then that’s surely a good thing rather than a negative.