Radeon RX 7900 XT 20 GB vs Radeon RX 7900 XTX 24 GB
Radeon RX 7900 XT has 20 GB memory, 800 GB/s bandwidth, 315 W nominal power; Radeon RX 7900 XTX has 24 GB memory, 960 GB/s bandwidth, 355 W nominal power. Compare model compatibility, like-for-like tokens/sec and ownership cost below.
Verdict
- throughputNo valid like-for-like performance comparison is available. The practical configurations below differ in quantization, runtime, context, settings, or evidence type, so their speed difference must not be attributed to hardware alone.
- capacityBoth machines run all 8 compared models in their best practical configurations. Compare their quantizations and evidence labels before treating any throughput difference as a hardware result.
- costAt 8 hours a day, the Radeon RX 7900 XT 20 GB has approximately 11% lower total monthly cost ($2 against $2), for a C corporation in United States (federal).
- evidenceThere are no comparable throughput rows, so this page makes no hardware-speed ranking. Practical deployment figures remain useful for fit planning but answer a different question.
- recommendationThroughput is close enough to be a wash, so this comes down to cost and capacity: the Radeon RX 7900 XT 20 GB is cheaper to own, and capacity differences above decide which models you can run at all.
Every statement above is generated from the calculations on this page by fixed rules — no prose is written for individual comparisons. If the numbers change, the verdict changes with them.
Hardware
| Radeon RX 7900 XT 20 GB | Radeon RX 7900 XTX 24 GB | |
|---|---|---|
| Purchase price estimate | — | — |
| Memory | 20 GB | 24 GB |
| Memory bandwidth | 800 GB/s | 960 GB/s |
| Usable bandwidth indicator | 560 GB/s (70%) | 672 GB/s (70%) |
| Nominal power | 315 W | 355 W |
| Measured load power | — | — |
| Idle power | — | — |
| Architecture | discrete gpu | discrete gpu |
Like-for-like performance0 comparable models
gpt-oss-20bDeepSeek Coder V2 Lite 16B-A2.4BMistral Small 3.2 24BDevstral Small 24BCodestral 22BInternLM 2.5 20BDeepSeek R1 Distill Qwen 14BQwen2.5 14B
| Model | Radeon RX 7900 XT 20 GB | Radeon RX 7900 XTX 24 GB | Winner |
|---|---|---|---|
| gpt-oss-20b 20.915B (3.6B active) | — no matched configuration | — no matched configuration | Not comparable |
| DeepSeek Coder V2 Lite 16B-A2.4B 15.706B (2.4B active) | — no matched configuration | — no matched configuration | Not comparable |
| Mistral Small 3.2 24B 24.011B | — no matched configuration | — no matched configuration | Not comparable |
| Devstral Small 24B 23.572B | — no matched configuration | — no matched configuration | Not comparable |
| Codestral 22B 22.247B | — no matched configuration | — no matched configuration | Not comparable |
| InternLM 2.5 20B 19.861B | — no matched configuration | — no matched configuration | Not comparable |
| DeepSeek R1 Distill Qwen 14B 14.77B | — no matched configuration | — no matched configuration | Not comparable |
| Qwen2.5 14B 14.77B | — no matched configuration | — no matched configuration | Not comparable |
Hardware deltas are calculated only when quantization, runtime, exact context, execution/decode mode and relevant inference settings match. Measured and estimated results are never compared to each other. A difference under 10% is reported as a tie.
Best practical configuration
| Model | Radeon RX 7900 XT 20 GB | Radeon RX 7900 XTX 24 GB | Practical result |
|---|---|---|---|
| gpt-oss-20b | — MXFP4 · estimated | — MXFP4 · estimated | Both fit; configurations may differ |
| DeepSeek Coder V2 Lite 16B-A2.4B | — Q5_K_M · estimated | — Q8_0 · estimated | Both fit; configurations may differ |
| Mistral Small 3.2 24B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Devstral Small 24B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Codestral 22B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| InternLM 2.5 20B | — Q4_K_M · estimated | — Q5_K_M · estimated | Both fit; configurations may differ |
| DeepSeek R1 Distill Qwen 14B | — Q5_K_M · estimated | — Q5_K_M · estimated | Both fit; configurations may differ |
| Qwen2.5 14B | — Q5_K_M · estimated | — Q5_K_M · estimated | Both fit; configurations may differ |
This is a deployment comparison: each machine uses its own recommended configuration. Different quantizations can change speed and quality, so these figures are not raw hardware benchmarks.
Economics — United States (federal), C corporation, 8h/day
| Radeon RX 7900 XT 20 GB | Radeon RX 7900 XTX 24 GB | |
|---|---|---|
| Purchase price estimate | — | — |
| Reclaimable VAT | $0 | $0 |
| Net cash at purchase | $0 | $0 |
| Monthly depreciation | $0.00 | $0.00 |
| Monthly electricity | $2.30 (16 kWh) | $2.59 (18 kWh) |
| Tax programme | §179 100.0% | §179 100.0% |
| Tax-programme benefit | $0 | $0 |
| Monthly economic cost | $1.81 | $2.05 |
| Total over 5 years | $109 | $123 |
Purchase prices are localized inputs in USD: tax/VAT excluded for Radeon RX 7900 XT 20 GB and tax/VAT excluded for Radeon RX 7900 XTX 24 GB. Net cash and monthly economic cost then apply the selected United States (federal) / C corporation tax treatment. Tax assumptions last verified 2026-09-07. Federal planning estimate only, not tax advice. State and local income tax, sales/use tax and incentives are excluded. It assumes 100% business use, a Section 179 election, enough business income to use it, and that the full annual limit remains available.