Both cards occupy the same rough price envelope on our dedicated GPU hosting, but the workloads where each one wins are very different. The RTX 5060 Ti 16GB is fresh Blackwell silicon with native FP8 and PCIe Gen 5; the RTX 3090 24GB is three-generation-old Ampere with a much bigger memory pool and nearly 2.1x the bandwidth. This guide walks through the decision one workload at a time and gives a concrete verdict at the end.
Contents
- Side-by-side specification
- Workload-by-workload winner
- LLM serving in detail
- Fine-tuning and training
- Power, heat and ops risk
- Verdict by buyer profile
Side-by-Side Specification
| Spec | RTX 5060 Ti 16GB | RTX 3090 24GB |
|---|---|---|
| Architecture | Blackwell GB206 | Ampere GA102 |
| CUDA cores | 4,608 | 10,496 |
| Tensor cores | 144 (5th gen) | 328 (3rd gen) |
| VRAM | 16 GB GDDR7 | 24 GB GDDR6X |
| Memory bandwidth | 448 GB/s | 936 GB/s |
| FP8 support | Native (HW) | Emulated only |
| PCIe | Gen 5 x8 | Gen 4 x16 |
| TDP | 180 W | 350 W |
| Launched | 2025 | 2020 |
Workload-by-Workload Winner
| Workload | Winner | Why |
|---|---|---|
| Llama 3.1 8B FP8 decode | 5060 Ti | Native FP8 beats emulation; 112 vs ~95 t/s |
| Llama 3 8B BF16 decode | 3090 | 2.1x bandwidth advantage; ~150 t/s AWQ |
| Qwen 2.5 14B AWQ | Draw | Both fit; 3090 faster, 5060 Ti more efficient |
| Qwen 2.5 32B AWQ | 3090 | Needs >16 GB VRAM, only 3090 holds it |
| Mixtral 8x7B int4 | 3090 | 24 GB capacity required |
| Long-context (32k+) | 3090 | KV cache headroom from extra 8 GB |
| SDXL 1024×1024 | 3090 | Bandwidth-bound image gen |
| LoRA fine-tune 7B | 5060 Ti | FP8 training path, lower power cost |
| QLoRA on 14B | 5060 Ti | Fits comfortably, efficient |
| Power per watt token | 5060 Ti | 180 W vs 350 W for similar work |
| Secondhand fleet risk | 5060 Ti | New silicon, warranty, no ex-mining |
LLM Serving in Detail
For an 8B model the 3090 wins raw throughput thanks to bandwidth – decode is memory-bound and 936 GB/s simply reads weights faster than 448 GB/s. But if the checkpoint is FP8-native, the 5060 Ti claws most of that back because half-precision weights halve the read volume per token. See FP8 deployment and the full benchmark comparison.
Above 14B parameters the 3090 is the only card of the two that still fits unquantised or at modest int4. Qwen 2.5 32B AWQ at ~20 GB or Mixtral 8x7B int4 at ~24 GB simply will not load on 16 GB.
Fine-Tuning and Training
LoRA and QLoRA favour the 5060 Ti. The BF16 and FP8 kernels on Blackwell are faster per watt, and Unsloth’s Blackwell-optimised path hits 2,600+ tokens/sec on Qwen 14B QLoRA. The 3090 runs the same training but draws roughly twice the wall power and lacks FP8 training kernels entirely. See QLoRA speeds.
Power, Heat and Ops Risk
- 180 W vs 350 W means roughly half the server-side cooling and PSU burden
- New silicon has manufacturer warranty; many 3090s on the used market saw heavy mining or gaming duty
- Blackwell is current-gen – expect 4-5 years of driver and CUDA toolkit support
- 3090 remains supported but is no longer a target platform for new kernel optimisations
Verdict by Buyer Profile
Pick the 5060 Ti if your target model fits in 16 GB, you care about FP8, and you want modern driver support at half the power budget. Pick the 3090 if your headline model is 20-32B class or long-context, and bandwidth-bound decode matters more than efficiency.
Modern Mid-Tier Blackwell
16 GB, native FP8, 180 W, new-gen drivers. UK dedicated hosting.
Order the RTX 5060 Ti 16GBSee also: 5060 Ti vs 3090 benchmark, Llama 3 8B benchmark, FP8 deployment, vLLM setup, first-day checklist.
