AMD Radeon HD 7970 vs AMD Radeon RX 480 Comparison

Where Each One Wins

The benchmark data splits these two AMD cards along a clear generational line. The AMD Radeon HD 7970, built on the original GCN architecture, posts a Geekbench OpenCL score of 34,541. The AMD Radeon RX 480, representing GCN 4.0, counters with 37,998 in the same test — a 9.1% advantage. That single head-to-head result is the only direct comparison available, and it goes to the newer card.

The RX 480’s win is not marginal in context. Its average benchmark score across all tests sits at 33,997, while the HD 7970’s average is 34,541. Interestingly, the HD 7970 actually holds a slightly higher average because the RX 480’s additional benchmarks — including a 3DMark Steel Nomad DX12 score of 966, a Geekbench Metal score of 51,057, and a Geekbench Vulkan score of 45,968 — pull its mean down. The HD 7970 only has the one OpenCL result, so its average equals that single score.

Where each card wins depends on the workload. The HD 7970 wins in raw average benchmark consistency, sitting at the 79th percentile of all GPUs. The RX 480 sits just one point lower at the 78th percentile, but it wins in every direct comparison where both have data. The RX 480’s OpenCL advantage is the headline, but its Vulkan and Metal scores suggest broader API coverage — the HD 7970 has no recorded results in those tests. For OpenCL compute, the RX 480 is decisively ahead. For legacy compatibility, the HD 7970 still holds its own against modern rivals, trailing the NVIDIA T1000 8 GB by just 0.1% and the NVIDIA A2 by 0.4%, while beating the NVIDIA TITAN V by 0.5% and the NVIDIA RTX A1000 by 1%.

Architecture Differences

The architectural gap between these two cards is substantial, spanning two full GCN revisions. The HD 7970 uses the Tahiti chip on GCN 1.0, fabricated on TSMC’s 28 nm process. It packs 4,313 million transistors into a 352 mm² die, yielding a transistor density of 12.3 million per square millimeter. The RX 480 switches to the Ellesmere chip on GCN 4.0, built on GlobalFoundries’ 14 nm process. That newer node allows 5,700 million transistors in a smaller 232 mm² die, achieving 24.6 million transistors per square millimeter — double the density of the older card.

Shading resources favor the RX 480. It carries 2,304 shading units and 144 texture mapping units, versus 2,048 shaders and 128 TMUs on the HD 7970. Both cards have 32 ROPs. The RX 480’s clock advantage is significant: it runs a 1,120 MHz base and 1,266 MHz boost, while the HD 7970’s base and boost clocks are not listed in the data. That clock headroom translates directly to throughput. The RX 480 delivers 5.834 TFLOPS of FP32 compute and 5.834 TFLOPS of FP16 (at a 1:1 ratio), against the HD 7970’s 3.789 TFLOPS FP32. Pixel rate jumps from 29.60 GPixel/s on the HD 7970 to 40.51 GPixel/s on the RX 480, and texture rate rises from 118.4 GTexel/s to 182.3 GTexel/s.

Memory configurations differ in capacity and bus width but land at nearly identical bandwidth. The HD 7970 uses 3 GB of GDDR5 on a 384-bit bus, achieving 264.0 GB/s. The RX 480 uses 8 GB of GDDR5 on a 256-bit bus, achieving 256.0 GB/s — a mere 3% deficit in bandwidth despite the narrower interface. Memory clocks are listed as 1,375 MHz (5.5 Gbps effective) for the HD 7970 and 2,000 MHz (8 Gbps effective) for the RX 480.

Power and physical specs also diverge sharply. The HD 7970 has a 250 W TDP, requires a 600 W suggested PSU, and needs both a 6-pin and an 8-pin power connector. The RX 480 draws 150 W, suggests a 450 W PSU, and uses only a single 6-pin connector. The RX 480 is also more compact: 240 mm long, 95 mm tall, and 35 mm wide, versus 275 mm, 111 mm, and 38 mm for the HD 7970. Both are dual-slot cards on PCIe 3.0 x16.

API support favors the newer card. The RX 480 supports DirectX 12 (12_0) and Vulkan 1.3, while the HD 7970 is limited to DirectX 12 (11_1) and Vulkan 1.2.170. Both support OpenGL 4.6. Display outputs differ too: the HD 7970 offers 1x DVI, 1x HDMI 1.4a, and 2x mini-DisplayPort 1.2, while the RX 480 provides 1x HDMI 2.0b and 3x DisplayPort 1.4a.

The Verdict

The data points to a clear pick for most users: the AMD Radeon RX 480. It wins the only direct head-to-head benchmark by 9.1% in Geekbench OpenCL, delivers over 50% more FP32 compute (5.834 TFLOPS vs 3.789 TFLOPS), and doubles the memory capacity to 8 GB. It also cuts power draw by 100 W, from 250 W to 150 W, and fits in a shorter, slimmer package. The RX 480’s Vulkan 1.3 and DirectX 12 (12_0) support make it the more future-proof option for modern workloads.

The HD 7970’s case rests on legacy value and raw bandwidth. Its 384-bit bus yields 264.0 GB/s, marginally higher than the RX 480’s 256.0 GB/s. Its average benchmark score of 34,541 edges out the RX 480’s 33,997, and its 79th percentile ranking is one point higher. For users running older software that predates GCN 4.0 optimizations, the HD 7970 remains competitive — it trades blows with the NVIDIA T1000 8 GB (-0.1%), NVIDIA A2 (-0.4%), and beats the NVIDIA TITAN V (+0.5%) and NVIDIA RTX A1000 (+1%) in OpenCL.

Choose the RX 480 for compute performance, modern API support, efficiency, and memory capacity. Choose the HD 7970 only if you specifically need that extra 8 GB/s of bandwidth or are building a period-correct legacy system. In virtually every measurable category that matters for current workloads, the RX 480 is the superior card.

FAQ

Q: Which card has the higher Geekbench OpenCL score?

A: The AMD Radeon RX 480 scores 37,998, which is 9.1% higher than the AMD Radeon HD 7970’s 34,541.

Q: How do the two cards compare in average benchmark performance?

A: The HD 7970 has a higher average benchmark score of 34,541 compared to the RX 480’s 33,997, despite losing the direct head-to-head OpenCL test.

Q: What is the memory capacity and bandwidth difference?

A: The HD 7970 has 3 GB of GDDR5 on a 384-bit bus with 264.0 GB/s bandwidth. The RX 480 has 8 GB of GDDR5 on a 256-bit bus with 256.0 GB/s bandwidth.

Q: Which card has better API support?

A: The RX 480 supports DirectX 12 (12_0) and Vulkan 1.3, while the HD 7970 is limited to DirectX 12 (11_1) and Vulkan 1.2.170. Both support OpenGL 4.6.

Q: How do power requirements differ between the two cards?

A: The HD 7970 has a 250 W TDP and requires a 600 W suggested PSU with 1x 6-pin and 1x 8-pin connectors. The RX 480 has a 150 W TDP, requires a 450 W suggested PSU, and uses only a single 6-pin connector.

Q: Which card performs better in Vulkan and Metal benchmarks?

A: Only the RX 480 has recorded scores in those tests: 45,968 in Geekbench Vulkan and 51,057 in Geekbench Metal. The HD 7970 has no data for either benchmark.

Head-to-Head Benchmarks

The sole direct comparison between these two cards is the Geekbench OpenCL test, and it paints a decisive picture. The RX 480 scores 37,998 against the HD 7970’s 34,541, a 9.1% margin. That gap is substantial for a compute-oriented benchmark, reflecting the architectural leap from GCN 1.0 to GCN 4.0. The RX 480’s 5.834 TFLOPS FP32 throughput versus 3.789 TFLOPS on the HD 7970 — a 54% advantage — explains much of the delta, even accounting for the narrower 256-bit memory bus.

The HD 7970 does have one statistical win: its average benchmark score. With only the OpenCL result on record, its average sits at 34,541. The RX 480’s average of 33,997 is dragged down by its 3DMark Steel Nomad DX12 score of 966, which is far lower than its compute scores. That anomaly aside, the RX 480 wins every test where both cards have data.

Context from the nearest rivals reinforces the HD 7970’s continued relevance. The HD 7970’s OpenCL score of 34,541 places it within 0.1% of the NVIDIA T1000 8 GB (34,561) and 0.4% of the NVIDIA A2 (34,690). It actually outperforms the NVIDIA TITAN V (34,355) by 0.5% and the NVIDIA RTX A1000 (34,207) by 1%. The RX 480’s nearest rivals tell a similar story of tight clustering: it leads the AMD Radeon HD 7950 (33,951) by 0.1%, trails the AMD Radeon RX 560 XT (34,133) by 0.4%, leads the AMD Radeon RX 7700S (33,849) by 0.4%, and trails the NVIDIA RTX A2000 12 GB (34,154) by 0.5%.

In practical terms, the RX 480’s 9.1% OpenCL lead translates to faster compute workloads, while its 8 GB frame buffer gives it a clear advantage in memory-heavy tasks. The HD 7970’s 264.0 GB/s bandwidth is technically higher, but the 8 GB/s difference is negligible in real-world scenarios. The RX 480 also offers superior pixel fill (40.51 GPixel/s vs 29.60 GPixel/s) and texture fill (182.3 GTexel/s vs 118.4 GTexel/s), making it the stronger card for rasterization-heavy workloads as well. The only area where the HD 7970’s architecture remains competitive is in raw memory bandwidth per clock, but that advantage does not translate into benchmark wins.