AMD Radeon Pro W5500X vs AMD Radeon RX 6600 XT Comparison

The AMD Radeon Pro W5500X and the AMD Radeon RX 6600 XT are both end-of-life, 8 GB GDDR6 cards built on TSMC's 7 nm process, and on paper they look like cousins. The recorded data tells a different story: the RX 6600 XT dominates the single shared benchmark by a wide margin, while the W5500X occupies a specialist niche as a workstation card built around Apple's MPX interface. This comparison breaks down where each card's strengths actually lie, based strictly on the measurements in the database.

FAQ

Q: Which card is faster in the benchmarks the database holds for both?

A: The RX 6600 XT. In Geekbench Metal, the only test with recorded results for both cards, the RX 6600 XT scored 88720 against the W5500X's 27973, a gap of 68.5 percent in the RX 6600 XT's favor.

Q: Do these cards use the same memory configuration?

A: They share the same capacity and type, 8 GB of GDDR6 on a 128-bit bus, but not the same speed. The W5500X runs its memory at 1750 MHz (14 Gbps effective) for 224.0 GB/s of bandwidth, while the RX 6600 XT runs at 2000 MHz (16 Gbps effective) for 256.0 GB/s.

Q: Which card supports ray tracing?

A: Only the RX 6600 XT. It carries 32 RT cores as part of its RDNA 2.0 architecture and supports DirectX 12 Ultimate (12_2). The W5500X, on RDNA 1.0, lists no RT cores and tops out at DirectX 12 (12_1).

Q: Can I put either card in a standard PC?

A: No. The W5500X uses the Apple MPX bus interface and offers 2x HDMI 2.0b outputs, marking it as a Mac Pro workstation part. The RX 6600 XT uses PCIe 4.0 x8 with 1x HDMI 2.1 and 3x DisplayPort 1.4a, a conventional desktop configuration.

Q: How do their power requirements compare?

A: The W5500X has a 125 W TDP with a suggested 300 W PSU. The RX 6600 XT raises that to a 160 W TDP, a single 8-pin power connector, and a suggested 450 W PSU.

Q: Which card sits higher in the database percentile rankings?

A: Interestingly, the W5500X, at the 73rd percentile against all GPUs, edges the RX 6600 XT at the 70th percentile, even though the RX 6600 XT wins the shared benchmark decisively. The percentile figures and the head-to-head result measure different things, and the direct Geekbench Metal comparison is the more reliable indicator of relative performance between these two.

Architecture Differences

Both GPUs come from AMD and both were fabricated by TSMC on a 7 nm process, but they represent two different generations of the RDNA lineage. The W5500X is a Navi 14 part on RDNA 1.0, released in December 2019 as a Radeon Pro Mac product. The RX 6600 XT is a Navi 23 part on RDNA 2.0, released in July 2021 as a member of the Radeon RX 6000 series, with the Navi architecture as its predecessor and Navi III as its successor.

The generational gap shows up in the silicon. The W5500X packs 6,400 million transistors into a 158 mm² die, a density of 40.5M per mm². The RX 6600 XT nearly doubles the transistor count to 11,060 million across a larger 237 mm² die, and its 46.7M per mm² density reflects the more mature design. That extra silicon buys real resources: 2048 shading units versus 1536, 128 texture mapping units versus 96, and 64 render output units versus 32, exactly double the ROP count.

RDNA 2.0 also brings features RDNA 1.0 simply lacks. The RX 6600 XT has 32 RT cores for hardware ray tracing and supports DirectX 12 Ultimate (12_2), while the W5500X stops at DirectX 12 (12_1) with no RT hardware listed. Both support OpenGL 4.6 and Vulkan 1.4, so the API gap is specifically at the DirectX feature level and ray tracing tier.

Clock speeds diverge sharply too. The W5500X runs a 1187 MHz base and 1757 MHz boost. The RX 6600 XT runs 1968 MHz base, 2359 MHz game clock, and 2589 MHz boost, meaning it operates at substantially higher frequencies across the board while also carrying more hardware per clock domain.

Head-to-Head Benchmarks

The database holds only one benchmark recorded for both cards, but it is not close. In Geekbench Metal, the RX 6600 XT scored 88720 and the W5500X scored 27973, a 68.5 percent margin for the RX 6600 XT. That is a rout, not a squeaker, and it is consistent with what the raw specifications predict: the RX 6600 XT delivers 10.60 TFLOPS of FP32 compute against 5.398 TFLOPS for the W5500X, and 21.21 TFLOPS FP16 against 10.80 TFLOPS, roughly double in both cases.

The throughput numbers reinforce the picture. The RX 6600 XT manages 165.7 GPixel/s and 331.4 GTexel/s, versus 56.22 GPixel/s and 168.7 GTexel/s for the W5500X. The pixel rate advantage is nearly triple, helped by the doubled ROP count and much higher clocks, and the memory subsystem feeds it better with 256.0 GB/s against 224.0 GB/s.

The RX 6600 XT's broader benchmark record adds context. It posted 80503 in Geekbench OpenCL, 72417 in Geekbench Vulkan, 16461 in PassMark G3D, 7520 in PassMark GPU Compute, 1804 in 3DMark Steel Nomad DX12, and 912 in PassMark G2D, plus PassMark DirectX scores of 194 (DX9), 109 (DX10), 163 (DX11), and 61 (DX12). The W5500X has no comparable entries beyond Metal, so cross-API comparison is limited to the one shared test.

Against their respective nearest rivals, both cards sit in tightly packed clusters. The W5500X's rivals include the NVIDIA GeForce GTX 980 Ti (28020, a 0.2 percent edge over the W5500X), the AMD Radeon RX 7800M (27883, 0.3 percent behind), the AMD Radeon Pro Vega 20 (27839, 0.5 percent behind), and the AMD FirePro S7150 (28117, 0.5 percent ahead). The RX 6600 XT's rivals include the NVIDIA GeForce GTX 1630 (24277, 0.7 percent behind), the Intel Arc A350M (24647, 0.8 percent ahead), the NVIDIA GeForce GTX 780 Ti (24236, 0.8 percent behind), and the NVIDIA GeForce RTX 2080 SUPER (24170, 1.1 percent behind).

Specification Differences

• Bus interface: Apple MPX on the W5500X versus PCIe 4.0 x8 on the RX 6600 XT. This is the single most consequential difference for compatibility.
• Display outputs: 2x HDMI 2.0b versus 1x HDMI 2.1 and 3x DisplayPort 1.4a.
• Shading units: 1536 versus 2048.
• TMUs: 96 versus 128.
• ROPs: 32 versus 64.
• RT cores: none listed versus 32.
• Base and boost clocks: 1187 MHz and 1757 MHz versus 1968 MHz and 2589 MHz, with the RX 6600 XT also listing a 2359 MHz game clock.
• Memory speed and bandwidth: 1750 MHz (14 Gbps effective) and 224.0 GB/s versus 2000 MHz (16 Gbps effective) and 256.0 GB/s.
• Transistors, die size, density: 6,400 million on 158 mm² at 40.5M per mm² versus 11,060 million on 237 mm² at 46.7M per mm².
• TDP and PSU: 125 W with a 300 W suggested PSU versus 160 W with a 450 W suggested PSU and a 1x 8-pin connector.
• Theoretical throughput: 5.398 TFLOPS FP32 and 10.80 TFLOPS FP16 versus 10.60 TFLOPS FP32 and 21.21 TFLOPS FP16; 56.22 GPixel/s and 168.7 GTexel/s versus 165.7 GPixel/s and 331.4 GTexel/s.
• DirectX support: 12 (12_1) versus 12 Ultimate (12_2).
• Physical dimensions: the RX 6600 XT lists 190 mm length, 110 mm height, and 40 mm width; the W5500X lists no dimensions. Both are dual-slot cards.
• Release timing: December 2019 versus July 2021.
• Launch MSRP: 599 USD for the W5500X, 379 USD for the RX 6600 XT.

The Verdict

For a conventional desktop PC builder, the data points one direction: the RX 6600 XT. It wins the only shared benchmark by 68.5 percent, doubles the FP32 and FP16 compute, nearly triples the pixel fill rate, adds hardware ray tracing with 32 RT cores, supports DirectX 12 Ultimate, and connects via standard PCIe 4.0 x8 with modern display outputs including HDMI 2.1 and three DisplayPort 1.4a connectors. Its higher 160 W TDP and 450 W PSU recommendation are modest asks for the performance on record.

The W5500X is not really a rival in that race, because it was never built for it. Its Apple MPX interface means it belongs in a Mac Pro workstation context, and its identity is that of a professional part from the Radeon Pro Mac line. Against its own nearest rivals, the GTX 980 Ti, RX 7800M, Radeon Pro Vega 20, and FirePro S7150, it sits within a fraction of a percent on aggregate scores, which tells you it was positioned squarely in the middle of that professional cluster rather than at the performance frontier. If the machine is a Mac Pro with an MPX slot and the workload is a Mac-based professional environment, the W5500X is the only one of these two that fits at all.

Both cards are end-of-life, so either purchase is a secondhand or remaining-stock proposition. Between them, the benchmark record leaves no ambiguity about raw capability, and the interface difference leaves no ambiguity about where each one can physically go.

Where Each One Wins

The RX 6600 XT wins on:

• Raw performance, decisively: 88720 versus 27973 in Geekbench Metal, a 68.5 percent margin.
• Compute throughput: 10.60 TFLOPS FP32 and 21.21 TFLOPS FP16, roughly double the W5500X's figures.
• Gaming-relevant fill rates: 165.7 GPixel/s and 331.4 GTexel/s.
• Ray tracing: 32 RT cores and DirectX 12 Ultimate (12_2) support.
• Memory bandwidth: 256.0 GB/s versus 224.0 GB/s on the same 8 GB GDDR6, 128-bit configuration.
• PC compatibility and connectivity: PCIe 4.0 x8, HDMI 2.1, and 3x DisplayPort 1.4a, in a compact 190 mm long, dual-slot card.
• Any workload where the extra recorded benchmark coverage matters, since the database holds results spanning Vulkan, OpenCL, 3DMark Steel Nomad, and multiple PassMark suites for it.

The W5500X wins on:

• Mac Pro compatibility, full stop: the Apple MPX interface makes it the only option of the two for that platform.
• Lower power draw: a 125 W TDP and a 300 W suggested PSU against 160 W and 450 W.
• Marginally higher database percentile placement, 73rd versus 70th against all GPUs, though the direct head-to-head result outweighs this.
• Its position within the professional cluster, sitting within half a percent of the GTX 980 Ti, RX 7800M, Radeon Pro Vega 20, and FirePro S7150 on aggregate scores.

In short, the W5500X is a platform-specific professional part with modest throughput, and the RX 6600 XT is a much faster mainstream GPU that only makes sense in a standard PCIe machine. The shared benchmark settles the performance question; the bus interface settles the compatibility question.