RTX 4070 Ti SUPER vs RTX 3090
The RTX 3090 holds 43 models from our catalog that the RTX 4070 Ti SUPER cannot fit at Q4_K_M, and decodes about 1.4× faster on memory bandwidth. Decode speed on a memory-bound workload scales with bandwidth, so that ratio is the number that matters once the model fits at all.
Specs side by side
| Spec | RTX 4070 Ti SUPER | RTX 3090 |
|---|---|---|
| VRAM | 16 GB | 24 GB |
| Memory bandwidth | 672 GB/s | 936 GB/s |
| TDP | 285 W | 350 W |
| Models that fit (Q4_K_M) | 374 of 506 | 417 of 506 |
What the extra VRAM actually buys
43 models in our catalog fit on the RTX 3090 at Q4_K_M but not on the RTX 4070 Ti SUPER. The largest of them:
Seed-OSS 36B InstructAya 23 35B ChatCommand R 35B (v01) ChatLLaVA-NeXT 34B v1.6Yi VL 34B ChatYi 34B
Largest model each can run
At Q4_K_M the biggest fit in our catalog is Mistral Small 24B (3.1) Instruct (15.0 GB) on the RTX 4070 Ti SUPER, and Seed-OSS 36B Instruct (22.1 GB) on the RTX 3090. Both figures are weights plus runtime overhead; KV cache for your context is extra.
Power and running cost
At 8 hours a day the RTX 4070 Ti SUPER draws about 68 kWh a month against 84 kWh for the RTX 3090 — a difference of 16 kWh. Multiply by your own tariff; we do not assume one. Board TDP is the rated figure, not measured draw.
FAQ
RTX 4070 Ti SUPER vs RTX 3090: which should I buy for local AI?
The RTX 3090 fits 417 of the 506 models in our catalog at Q4_K_M against 374 for the RTX 4070 Ti SUPER, and has about 1.4× the memory bandwidth, which is what sets decode speed once a model fits. If the models you run already fit the RTX 4070 Ti SUPER, the extra spend buys context length and speed, not a new model tier.
Is the RTX 3090 faster than the RTX 4070 Ti SUPER?
On memory-bound decoding, yes — roughly 1.4× the throughput, since token generation scales with memory bandwidth (936 GB/s vs 672 GB/s). This is an upper bound from bandwidth alone, not a measured benchmark.
How much more VRAM does the RTX 3090 have?
8 GB more (24 GB vs 16 GB). That difference lets it hold 43 additional models from our catalog at Q4_K_M.
Need a third card in the mix? The interactive compare tool lines up any three. To size KV cache for your context length, use the GPU Memory Calculator.
Related matchups
Other head-to-heads involving these cards:
RTX 3090 vs RTX 4090RTX 3090 vs RTX 5090RTX 4060 Ti 16GB vs RTX 4070 Ti SUPERRTX 4070 Ti SUPER vs RTX 4090RTX 4060 Ti 16GB vs RTX 3090
New to sizing? What VRAM is and why bandwidth sets decode speed cover the basics, and quantization explains the formats in the table above. Common mistakes when sizing VRAM lists the traps.