Radeon RX 6800 16 GB vs Radeon RX 6900 XT 16 GB
Radeon RX 6800 has 16 GB memory, 512 GB/s bandwidth, 250 W nominal power; Radeon RX 6900 XT has 16 GB memory, 512 GB/s bandwidth, 300 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 6800 16 GB has approximately 17% lower total monthly cost ($1 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 6800 16 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 6800 16 GB | Radeon RX 6900 XT 16 GB | |
|---|---|---|
| Purchase price estimate | — | — |
| Memory | 16 GB | 16 GB |
| Memory bandwidth | 512 GB/s | 512 GB/s |
| Usable bandwidth indicator | 358 GB/s (70%) | 358 GB/s (70%) |
| Nominal power | 250 W | 300 W |
| Measured load power | — | — |
| Idle power | — | — |
| Architecture | discrete gpu | discrete gpu |
Like-for-like performance0 comparable models
gpt-oss-20bDeepSeek Coder V2 Lite 16B-A2.4BDeepSeek R1 Distill Qwen 14BQwen2.5 14BQwen2.5 Coder 14BQwen3 14BPhi-4 14BPhi-3 Medium 14B
| Model | Radeon RX 6800 16 GB | Radeon RX 6900 XT 16 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 |
| 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 |
| Qwen2.5 Coder 14B 14.77B | — no matched configuration | — no matched configuration | Not comparable |
| Qwen3 14B 14.768B | — no matched configuration | — no matched configuration | Not comparable |
| Phi-4 14B 14.66B | — no matched configuration | — no matched configuration | Not comparable |
| Phi-3 Medium 14B 13.96B | — 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 6800 16 GB | Radeon RX 6900 XT 16 GB | Practical result |
|---|---|---|---|
| gpt-oss-20b | — MXFP4 · estimated | — MXFP4 · estimated | Both fit; configurations may differ |
| DeepSeek Coder V2 Lite 16B-A2.4B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| DeepSeek R1 Distill Qwen 14B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Qwen2.5 14B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Qwen2.5 Coder 14B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Qwen3 14B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Phi-4 14B | — Q4_K_M · estimated | — Q4_K_M · estimated | Both fit; configurations may differ |
| Phi-3 Medium 14B | — Q4_K_M · estimated | — Q4_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 6800 16 GB | Radeon RX 6900 XT 16 GB | |
|---|---|---|
| Purchase price estimate | — | — |
| Reclaimable VAT | $0 | $0 |
| Net cash at purchase | $0 | $0 |
| Monthly depreciation | $0.00 | $0.00 |
| Monthly electricity | $1.82 (13 kWh) | $2.19 (16 kWh) |
| Tax programme | §179 100.0% | §179 100.0% |
| Tax-programme benefit | $0 | $0 |
| Monthly economic cost | $1.44 | $1.73 |
| Total over 5 years | $86 | $104 |
Purchase prices are localized inputs in USD: tax/VAT excluded for Radeon RX 6800 16 GB and tax/VAT excluded for Radeon RX 6900 XT 16 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.