Hi guys! I just received my RTX 4090 (after spending my right kidney on it) today and I am BLOWN AWAY by the frame generation. Total game changer. 60+ FPS at KJFK with ultra settings.
Anyway, I noticed now that I am severely limited by the main thread (above 30ms on it) pretty much anywhere I go and with frame generation off, only get in like the 20’s FPS wise.
My question to you guys is, my power supply is I think 850 watts. It is possible that I don’t have sufficient power to the PC and performance is suffering because of it? Or do you guys think it is just a matter of the 4090 being way too powerful and bottle necking the i9?
Put your build into PCPartPicker including fans, cooler, storage… everything. It will tell you your power consumption (not including any overclocking).
You are probably more likely limited by your CPU than GPU, regardless of power supply.
It shouldn’t have anything to do with the PSU. A 4090 generally draws below 400 Watts in most situations and a 850 Watt PSU can handle that no problem if it is a decent model and all the cables are connected the right way.
The problem is, that the MSFS right now has pretty bad performance at airports, especially if you use a lot of AI traffic. It got somewhat better with the recent patch, but it is still not particularly great and most likely it is just one of the CPU threads that limits performance for the rest of the system.
That’s not quite how that works. The first sign of an overloaded PSU are random shutdowns and restarts due to the built-in OPP/OCP within your PSU. If you are not getting these, your PSU is operating under ideal conditions.
An 850W PSU for a 4090 and 12900k should be fine assuming you don’t heavily overclock your 4090 by raising the power limit - keep it at 100%, which should be 450W for a 4090. The 12900k should be consuming roughly 100W during MSFS use. For comparison, I have an overclocked 13900K and max 600W power limit in my 4090, and the most my system draws is 700W according to my UPS. Usually my GPU consumes around 500W on MSFS, 100W for the 13900K, and I’m guessing an additional 100W for the rest of the components.
The 12900k is more than adequate for a 4090 - I wouldn’t worry about bottleneck with this setup.
How about an 11700K? I’ve been contemplating upgrading from a 3080Ti to a 4090 as prices are getting reasonable and stock is available. I fly 4K and HP Reverb G2… mostly GA and Warbirds over the Northeast US / Boston and New York City up to Maine. Sometimes Arizona and California and across the country multi-day trips.
The important feature are not watts, even if they are relevant, but how many amps it’s able to provide via the pci-e plugs for the card alone (the 12V output). If your 12V output is too weak and you also have other components using it you may find that card is not performing optimally. This shouldn’t happen in most cases nowadays but just check what you have connected in your case to the pci-e plugs to be sure.
Anyway I have same cpu+gpu (12900ks indeed) and both typically eat 200W+400W in most cases for MSFS. I have a 1200W psu (Corsair HX 1200) than can give 100A on the 12V output, but 1000W is the recommended one. I wouldn’t go below 1000W because some cards come with a factory OC that allows them to go higher than the official baseline. That way you are on the safe side. The cost of the PSU is low but it’s the heart of your whole system.