3090 vs 4070 ti super upgrade?

V91 · January 9

Seriously considering a graphics card upgrade. When I built my system in late 2018 I went with a then-last-gen 1070 ti and 8700K.

These days I'm looking to get into desktop VR and am currently running Stable Diffusion (SD) for image generation, as well as some gaming here and there at 1440p.

With the new 40 series super cards on the horizon, I spent a good bit of time comparing specs sheets today and am stuck between considering buying a used 3090 on ebay for ~$800 USD or waiting and getting the upcoming 4070 ti super for (fingers crossed F*** scalpers) also $800 USD. The 3090 has 24GB memory which is better for training models and I believe better for running SD in general. It also has a bigger memory bus and more CUDA cores by ~2000. But the 40 card would have the newer DLSS and I know that 30 series CUDA cores aren't the same as 40 series CUDA cores. NVIDIA's cherry-picked carts would have me believe that the 4070 ti super will be ~30-40% 'faster' overall than the 3090, but I have serious doubts.

I could also upgrade my CPU to up to a 9900K according to MSI's website if it would be a major bottleneck.

Thoughts from the LTT community? Thanks!

Gat Pelsinger · January 9

@V91 It's upon you. If your workload needs a lot of VRAM, then definitely 3090. If you want DLSS and frame gen for games, then the Nvidia GeForce Ray Tracing Texel eXtreme 4070 Titanium Super would be a better choice. It is a bit faster in raw performance but you also get a lot of VRAM on the 3090.

emosun · January 9

10 minutes ago, V91 said:

I could also upgrade my CPU to up to a 9900K according to MSI's website if it would be a major bottleneck.

a bottleneck only occurs through usage , not just parts simply existing in the machine.

i'd probably go 4070 for the reduced power usage. The 3090 runs real hot and thirsty

Mick Naughty · January 9

9900k struggles enough with a 3090. I get by in a few games but also not getting peak frames. I'd go cpu over gpu but since you just got it, could alway use a frame cap on the new card if need be.

V91 · January 9

@Gat Pelsinger I mean my 'workload' is all hobby stuff at this point. I'd probably prioritize gaming performance over AI side projects at this point, but thanks for the input!

@emosun Fair on the bottleneck. It seems a contentious subject based on reading through a few posts here before making mine. Hadn't even considered power usage, that's a good point.

@Mick Naughty Yeah, I just went and checked the userbenchmark.com on 8700k vs 9900K and it says there's only a 1% uplift going from one to the other. But also, going from an 8700k to a 14900k is still only showing a 48% uplift.

Which one would be better for running VR?

I'm a 'new computer every 5-8 years or when something breaks' kind of person, so I'd really rather not drop $1500+ on a whole new system (Mobo, RAM, CPU, GPU) if I don't really need to.

So, I guess my follow up question on bottleneck would be: Will my 8700k greatly bottleneck a potential 3090 or 4070 ti super upgrade in Stable Diffusion, light 2D gaming, and/or fairly heavy VR games?