RTX PRO 4000 Blackwell vs RTX 3090 Ti
Both run on the same nodes, the same templates and the same tiers here — so the choice comes down to memory, bandwidth and price. Every figure below is from the catalogue or the vendor datasheet.
- RTX PRO 4000
- $0.08/h24 GB · Blackwell · 16 available
- RTX 3090 Ti
- $0.06/h24 GB · Ampere · 24 available
- Price gap
- 25%On spot, per GPU-hour
- Over 100 h
- $2.00Difference for the same GPU-hours
What actually separates them.
Four differences that change a decision, computed from the numbers rather than asserted.
The RTX 3090 Ti costs 25% less per hour
$0.06 against $0.08 on spot — $2.00 of difference over 100 GPU-hours.
Token generation is faster on the RTX 3090 Ti
1,008 GB/s against 672 GB/s. Inference reads the whole model from memory for every token, so bandwidth, not FLOPS, usually sets the ceiling.
More memory per dollar on the RTX 3090 Ti
400 GB per dollar per hour against 300 GB. The usual tie-breaker when both cards fit the job.
Every figure we hold on both cards.
A row is marked only when both values exist and one is genuinely better. RTX PRO 4000 leads on 3 rows, RTX 3090 Ti on 7.
| RTX PRO 4000 Blackwell | RTX 3090 Ti | |
|---|---|---|
| GPU memoryDecides which models fit at all | 24 GB GDDR7 | 24 GB GDDR6X |
| Memory bandwidthSets token throughput on inference | 672 GB/s | 1,008 GB/s |
| FP32 | 37 TFLOPS | 40 TFLOPS |
| 8-bit float (FP8)Halves the memory a model needs, where the stack supports it | Supported | Not supported |
| Architecture | Blackwell (2025) | Ampere (2022) |
| Board powerLower is cheaper to run at scale — for us, not for your bill | 145 W | 450 W |
| GPU-to-GPU linkOnly matters for multi-GPU training | PCIe only | NVLink |
| Node sizes | 1×, 2×, 4× | 1×, 2×, 4× |
| Spot price | $0.08/h | $0.06/h |
| On-demand price | $0.15/h | $0.09/h |
| Memory per dollarGPU memory per $1 of spot time, per hour | 300 GB | 400 GB |
| 30-day reclaim rateShare of spot instances reclaimed | 5–10% | 10–15% |
| Available now | 16 GPUs | 24 GPUs |
Specifications come from each vendor's datasheet — linked on the RTX PRO 4000 page and the RTX 3090 Ti page. Prices are ours, per GPU-hour, billed per minute.
The same models, on one GPU of each.
Weights only, with 20% of the memory kept free for activations and the KV cache. A cross means one GPU is not enough — the model page has the multi-GPU arithmetic.
| Model | Precision | RTX PRO 4000 24 GB | RTX 3090 Ti 24 GB |
|---|---|---|---|
| Llama 3.1 8B8B parameters | FP16 · 16 GB | Fits | Fits |
| INT4 · 4 GB | Fits | Fits | |
| Qwen2.5 32B32B parameters | FP16 · 64 GB | Needs 4× node | Needs 4× node |
| INT4 · 16 GB | Fits | Fits | |
| Llama 3.3 70B70B parameters | FP16 · 140 GB | Needs more than one node | Needs more than one node |
| INT4 · 35 GB | Needs 2× node | Needs 2× node | |
| Mixtral 8x22B141B parameters | FP16 · 282 GB | Needs more than one node | Needs more than one node |
| INT4 · 71 GB | Needs 4× node | Needs 4× node |
The same 100 GPU-hours on each.
Compute only, billed per minute. Storage is $0.08 per GB-month on either card.
| RTX PRO 4000 | RTX 3090 Ti | |
|---|---|---|
| One hour, spot | $0.08 | $0.06 |
| One day, spot | $1.92 | $1.44 |
| 100 GPU-hours, spot | $8.00 | $6.00 |
| 100 GPU-hours, on-demand | $15.00 | $9.00 |
| A month, reserved | $65.70 | $43.80 |
Take the RTX PRO 4000 when…
- Fine-tuning small models — LoRA on 7B–13B models, and full fine-tuning below 3B.
- Image and video generation — Diffusion pipelines run entirely in memory at this capacity.
- Anything that can checkpoint — On the spot tier this model is 47% below its own on-demand price, with a 2-minute notice before a reclaim.
Take the RTX 3090 Ti when…
- Fine-tuning small models — LoRA on 7B–13B models, and full fine-tuning below 3B.
- Image and video generation — Diffusion pipelines run entirely in memory at this capacity.
- Multi-GPU jobs over NVLink — GPU-to-GPU traffic stays off the PCIe bus, which is what makes tensor and pipeline parallelism worth it.
RTX PRO 4000 or RTX 3090 Ti?
Which is cheaper, the RTX PRO 4000 or the RTX 3090 Ti?
The RTX 3090 Ti, at $0.06 per GPU-hour on spot against $0.08 — 25% less. On-demand: $0.09 against $0.15.
Which one should I take for inference?
Take the one that holds the model with room for the KV cache, then the one with more memory bandwidth. Here that is the RTX PRO 4000 on capacity (24 GB) and the RTX 3090 Ti on bandwidth.
Can I run both on the same job?
Not inside one instance — a node holds GPUs of a single model. You can run two instances in parallel, on the same persistent volume in turn, or split the work: a big card for the model that needs capacity, a cheap one for the parts that do not.
Other comparisons: the full list · all 47 models
Try both for less than the price of deciding.
An hour on each costs $0.14 on spot. Nothing renews, and your disk moves between them.
Billed per minute from the moment the instance is reachable. Minimum credit $40, no subscription.