NVIDIA Quadro RTX 4000 vs NVIDIA Tesla K20m Comparison

FAQ

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

A: The NVIDIA Tesla K20m posts an average benchmark score of 19089, while the NVIDIA Quadro RTX 4000 averages 17789. Despite the RTX 4000 winning every head-to-head benchmark listed, the K20m holds a higher aggregate average across all tested workloads, placing it at the 64th percentile versus the RTX 4000's 61st percentile.

Q: What is the single largest performance gap between the two cards in head-to-head testing?

A: In Geekbench OpenCL, the Quadro RTX 4000 scores 74540 against the Tesla K20m's 16241, a delta of -78.2% from the K20m's perspective. This means the RTX 4000 delivers roughly 4.6 times the OpenCL compute performance of the older Tesla card.

Q: Which card has more shading units, and does that translate to higher FP32 throughput?

A: The Tesla K20m has more shading units at 2496, compared to 2304 on the RTX 4000. However, the RTX 4000 still achieves substantially higher FP32 performance at 7.119 TFLOPS versus 3.524 TFLOPS, because its Turing architecture runs at much higher clock speeds — a 1005 MHz base and 1545 MHz boost, while the K20m lists no base or boost clock figures.

Q: What memory configuration differences exist between the two cards?

A: The Tesla K20m uses 5 GB of GDDR5 on a 320-bit bus, yielding 208.0 GB/s of bandwidth. The Quadro RTX 4000 uses 8 GB of GDDR6 on a 256-bit bus, delivering 416.0 GB/s — exactly double the bandwidth despite the narrower interface.

Q: Do both cards support the same modern graphics APIs?

A: No. The Tesla K20m supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175. The Quadro RTX 4000 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The RTX 4000's DirectX 12 Ultimate and newer Vulkan revision reflect its more recent architecture.

Q: How does the physical slot and power requirement differ?

A: The Tesla K20m is a dual-slot card requiring a 550 W suggested PSU and uses 1x 6-pin plus 1x 8-pin power connectors. The Quadro RTX 4000 is a single-slot card needing only a 450 W suggested PSU and a single 8-pin connector, while also featuring display outputs (3x DisplayPort 1.4a and 1x USB Type-C) — the Tesla has no display outputs.

Where Each One Wins

The Quadro RTX 4000 dominates every directly comparable benchmark in the dataset. In Geekbench OpenCL, it scores 74540 versus 16241 for the Tesla K20m, a massive advantage. In Geekbench Vulkan, the RTX 4000 scores 78844 versus 21936, again a decisive win. The RTX 4000 also has a much broader benchmark portfolio, including 3DMark Steel Nomad DX12 (1873), Passmark G3D (15117), and Passmark GPU Compute (6176), where no Tesla K20m scores exist for comparison.

The Tesla K20m's only statistical advantage is its higher average benchmark score (19089 versus 17789) and its slightly better percentile ranking (64th versus 61st). This aggregate edge comes from the fact that the K20m has only two benchmark results, both in the 16,000–22,000 range, while the RTX 4000's ten results include some lower scores like Passmark DirectX 9 (205) and Passmark DirectX 10 (108), which drag down its average. In terms of raw compute head-to-head, the K20m does not win a single listed comparison.

Architecture Differences

The two cards come from entirely different NVIDIA eras. The Tesla K20m uses the GK110 chip built on Kepler architecture at TSMC's 28 nm process. It packs 7,080 million transistors into a 561 mm² die, yielding a transistor density of 12.6M per mm². This is a compute-oriented Tesla generation card, part of the Tesla Kepler (Kxx) family, with no display outputs and no RT or tensor cores.

The Quadro RTX 4000 uses the TU104 chip on Turing architecture at TSMC's 12 nm node. It contains 13,600 million transistors in a 545 mm² die, for a much higher density of 25.0M per mm². Turing introduces dedicated hardware features that Kepler lacks entirely: 36 RT cores for ray tracing and 288 tensor cores for AI workloads. The RTX 4000 also supports FP16 compute at 14.24 TFLOPS (2:1 ratio), while the K20m lists no FP16 capability at all.

The process node difference is substantial — 28 nm versus 12 nm — which explains why the RTX 4000 delivers more than double the FP32 throughput (7.119 TFLOPS versus 3.524 TFLOPS) while consuming less power (160 W TDP versus 225 W). The RTX 4000 also uses GDDR6 memory versus GDDR5 on the K20m, and its PCIe interface is newer (PCIe 3.0 x16 versus PCIe 2.0 x16).

Specification Differences

The most striking specification gap is memory bandwidth: the RTX 4000 provides 416.0 GB/s versus 208.0 GB/s on the K20m — exactly double. Memory capacity also differs, with 8 GB on the RTX 4000 versus 5 GB on the K20m, and the memory type advances from GDDR5 to GDDR6. The effective memory clock on the RTX 4000 is 13 Gbps, versus 5.2 Gbps on the K20m.

Clock speeds are only listed for the RTX 4000 (base 1005 MHz, boost 1545 MHz); the K20m has no base or boost clock figures in the data. The RTX 4000 also has higher pixel rate (98.88 GPixel/s versus 36.71 GPixel/s) and texture rate (222.5 GTexel/s versus 146.8 GTexel/s), despite having fewer TMUs (144 versus 208) and fewer shading units (2304 versus 2496). ROPS favor the RTX 4000 at 64 versus 40.

Physical dimensions differ: the K20m is 267 mm (10.5 inches) long, while the RTX 4000 is 241 mm (9.5 inches) long and also lists a height of 111 mm (4.4 inches). The K20m is dual-slot; the RTX 4000 is single-slot. Power delivery requires 1x 6-pin + 1x 8-pin on the K20m versus a single 8-pin on the RTX 4000, with suggested PSU ratings of 550 W and 450 W respectively. The RTX 4000 has display outputs; the K20m has none.

Head-to-Head Benchmarks

Only two benchmark tests have results for both cards, and the Quadro RTX 4000 wins both decisively.

In Geekbench OpenCL, the RTX 4000 scores 74540 against the K20m's 16241. The deltaPct is -78.2%, meaning the K20m trails by over three-quarters of the RTX 4000's score. This is a compute-heavy workload, and the RTX 4000's combination of higher clocks, newer architecture, and double memory bandwidth produces an overwhelming advantage. The K20m's 2496 shading units cannot compensate for the massive clock and efficiency differences.

In Geekbench Vulkan, the RTX 4000 scores 78844 versus 21936 for the K20m, a deltaPct of -72.2%. The absolute gap is slightly smaller in percentage terms, but the RTX 4000 still more than triples the K20m's output. Vulkan performance benefits from the RTX 4000's newer API support (Vulkan 1.4 versus 1.2.175) and its superior fill rates — 98.88 GPixel/s versus 36.71 GPixel/s.

The RTX 4000 also has eight additional benchmark scores that the K20m lacks entirely. These include 3DMark Steel Nomad DX12 at 1873, Passmark G3D at 15117, Passmark GPU Compute at 6176, and several DirectX versions ranging from 52 (DX12) to 205 (DX9). The K20m has no comparable results, so it is impossible to determine how it would fare in these tests, but given its massive deficits in the two shared benchmarks, the pattern strongly suggests the RTX 4000 would win those as well.

The Verdict

The data points to a clear conclusion: the NVIDIA Quadro RTX 4000 is the superior performer in every measurable head-to-head comparison. Its Geekbench OpenCL score of 74540 is 4.6 times the K20m's 16241, and its Vulkan score of 78844 is 3.6 times the K20m's 21936. The RTX 4000 also offers double the memory bandwidth, double the FP32 throughput, and adds RT and tensor cores that the K20m lacks entirely.

The Tesla K20m's only statistical claim is its higher average benchmark score (19089 versus 17789) and better percentile (64th versus 61st). This is a quirk of having fewer benchmark results — the K20m's two scores are both mid-range, while the RTX 4000's ten scores include several low DirectX legacy tests (as low as 52 in Passmark DX12) that pull its average down. A buyer or system builder relying on the average score alone might misjudge the K20m as the better card, but the head-to-head data contradicts that.

Who should pick the Quadro RTX 4000? Anyone needing ray tracing, tensor core acceleration, modern API support (DirectX 12 Ultimate, Vulkan 1.4), display outputs, or significantly higher compute throughput. Its single-slot design, lower 160 W TDP, and 450 W PSU requirement also make it far easier to integrate into workstations. The RTX 4000 is also smaller at 241 mm versus 267 mm.

Who should pick the Tesla K20m? The data supports essentially no workload where it wins outright. Its only advantages are more shading units (2496 versus 2304) and more TMUs (208 versus 144), but these do not translate to any benchmark victory. The K20m's 5 GB of GDDR5 with 208.0 GB/s bandwidth is half the RTX 4000's capacity and half its bandwidth. Even its launch MSRP of 3,199 USD — versus 899 USD for the RTX 4000 — cannot be justified by its performance profile. The K20m is an end-of-life product from 2013, while the RTX 4000 is also end-of-life but from 2018, giving it five additional years of architectural advancement. For any compute task represented in this dataset, the RTX 4000 is the rational choice.