AMD Radeon R5 M255 vs NVIDIA GeForce GT 745M Comparison

NVIDIA GeForce GT 745M and AMD Radeon R5 M255 are both end-of-life mobile graphics solutions from the 2013-2014 era, built on the same 28 nm TSMC process. The recorded data shows a near-even split in benchmark victories, with each GPU claiming one win in the two shared tests. The NVIDIA part takes the Geekbench Vulkan test by a wide margin, while the AMD part dominates Geekbench OpenCL just as decisively. Average benchmark scores favor the Radeon R5 M255 (4788 versus 3953), placing it in the 28th percentile of all GPUs, compared to the GeForce GT 745M's 23rd percentile. Despite this overall average gap, the two parts are not cleanly separated in performance; the nature of the workload determines which one comes out ahead.

Where Each One Wins

The AMD Radeon R5 M255 is the clear winner in OpenCL compute workloads. In the Geekbench OpenCL test, it scores 4650 against the GeForce GT 745M's 3580, a delta of -23% from AMD's perspective (meaning the NVIDIA part trails by 23%). This is a substantial lead, roughly 30% ahead of the GT 745M in raw OpenCL throughput. The Radeon's higher FP32 rating, 721.9 GFLOPS versus 421.6 GFLOPS, aligns with this result. If a user's application relies heavily on OpenCL acceleration, the data points squarely at the AMD part.

The NVIDIA GeForce GT 745M wins the Vulkan test by a significant margin. Its Geekbench Vulkan score of 5502 dwarfs the Radeon R5 M255's 4925, a delta of 11.7% in NVIDIA's favor. This is a notable advantage in a modern graphics API, suggesting better driver optimization or architectural efficiency for Vulkan workloads. For gaming or compute tasks that use Vulkan, the GT 745M is the stronger choice according to the recorded benchmarks.

Beyond these two head-to-head tests, the overall average benchmark score favors AMD. The Radeon R5 M255's average of 4788 is higher than the GeForce's 3953. However, this average includes only the two tests listed in the database, so it is heavily influenced by the OpenCL result. The real takeaway is a split: AMD leads in OpenCL, NVIDIA leads in Vulkan. There is no single GPU that wins both.

Architecture Differences

The two GPUs come from different architectural generations. The NVIDIA GeForce GT 745M uses the GK107 chip, built on the Kepler architecture, and belongs to the GeForce 700M generation. The AMD Radeon R5 M255 uses the Topaz chip, built on the GCN 3.0 architecture, and belongs to the Gem System (R5 M200) generation. Both are fabricated on a 28 nm process at TSMC, but the transistor counts differ. The AMD chip packs 1,550 million transistors on a 125 mm² die, while the NVIDIA chip has 1,270 million transistors on a smaller 118 mm² die. This translates to a higher transistor density for AMD: 12.4M per mm² versus 10.8M per mm².

Shading unit counts are identical at 384, but the rest of the core configuration diverges. The NVIDIA part has 32 texture mapping units (TMUs) and 16 render output units (ROPs), while the AMD part has fewer of both: 24 TMUs and 8 ROPs. Despite fewer TMUs and ROPs, the AMD part achieves higher texture and pixel rates. The Radeon R5 M255 outputs 22.56 GTexel/s and 7.520 GPixel/s, while the GeForce GT 745M outputs 17.57 GTexel/s and 4.392 GPixel/s. This is possible because the AMD chip runs at a higher clock speed, which is a separate spec difference covered below.

Memory architecture also differs. The NVIDIA GT 745M uses 2 GB of GDDR5 memory on a 128-bit bus, yielding 64.00 GB/s of bandwidth. The AMD R5 M255 uses 2 GB of DDR3 memory on the same 128-bit bus, but the bandwidth is exactly half: 32.00 GB/s. The memory clock is 1000 MHz for both, but the effective data rate differs: 4 Gbps for NVIDIA's GDDR5 versus 2 Gbps for AMD's DDR3. This is a significant disadvantage for the AMD part in memory-intensive tasks.

API support differs as well. The AMD part supports DirectX 12 (12_0), while the NVIDIA part supports DirectX 12 (11_0). Both support OpenGL 4.6. Vulkan versions are close: NVIDIA lists 1.2.175, AMD lists 1.2.170. The bus interface also varies: NVIDIA uses PCIe 3.0 x16, while AMD uses PCIe 3.0 x8, a narrower link.

Head-to-Head Benchmarks

The two shared benchmark results paint a clear picture of complementary strengths. In Geekbench OpenCL, the AMD Radeon R5 M255 scores 4650, which is 23% higher than the GeForce GT 745M's 3580. This is the largest performance gap in either direction. For any OpenCL-based compute task, the AMD part offers a decisive advantage. The FP32 rating supports this: 721.9 GFLOPS for AMD versus 421.6 GFLOPS for NVIDIA. The AMD GPU is simply doing more floating-point work per second.

In Geekbench Vulkan, the tables turn. The NVIDIA GeForce GT 745M scores 5502, which is 11.7% higher than the AMD Radeon R5 M255's 4925. This is a solid lead, though not as large as AMD's OpenCL advantage. The Vulkan result is notable because the GT 745M has lower raw compute specs (FP32, texture rate, pixel rate) yet still beats the AMD part in this API. This suggests that NVIDIA's Kepler architecture, despite being older, handles Vulkan workloads more efficiently, or that driver maturity plays a role. The data does not explain the cause, only the outcome.

The average benchmark score, which combines these two tests, favors AMD at 4788 versus 3953. However, this average is skewed by the OpenCL result's magnitude. If a user only cares about Vulkan, the GT 745M is the better part. If OpenCL is the priority, the R5 M255 is the obvious pick. There is no middle ground in the recorded data.

Specification Differences

The following fields differ between the two GPUs in the database:

• Chip: GK107 (NVIDIA) versus Topaz (AMD)
• Architecture: Kepler versus GCN 3.0
• Generation: GeForce 700M versus Gem System (R5 M200)
• Transistors: 1,270 million versus 1,550 million
• Die size: 118 mm² versus 125 mm²
• Transistor density: 10.8M / mm² versus 12.4M / mm²
• Base clock: Not listed for NVIDIA versus 925 MHz for AMD
• Boost clock: Not listed for NVIDIA versus 940 MHz for AMD
• Memory type: GDDR5 versus DDR3
• Memory effective rate: 4 Gbps versus 2 Gbps
• Memory bandwidth: 64.00 GB/s versus 32.00 GB/s
• TMUs: 32 versus 24
• ROPs: 16 versus 8
• Pixel rate: 4.392 GPixel/s versus 7.520 GPixel/s
• Texture rate: 17.57 GTexel/s versus 22.56 GTexel/s
• FP32: 421.6 GFLOPS versus 721.9 GFLOPS
• FP16: Not listed for NVIDIA versus 721.9 GFLOPS (1:1) for AMD
• TDP: 45 W for NVIDIA versus not listed for AMD
• Slot width: IGP for NVIDIA versus not listed for AMD
• Bus interface: PCIe 3.0 x16 versus PCIe 3.0 x8
• Display outputs: Portable Device Dependent for NVIDIA versus not listed for AMD
• DirectX support: 12 (11_0) versus 12 (12_0)
• Vulkan version: 1.2.175 versus 1.2.170
• Release date: 2013-03-31 versus 2014-10-11
• Predecessor: GeForce 600M versus Solar System
• Successor: GeForce 800M versus Polaris Mobile

The GT 745M has a higher memory bandwidth and more ROPs, while the R5 M255 has higher clock speeds, more transistors, higher FP32, and better texture and pixel rates. The NVIDIA part also has a listed TDP of 45 W, while the AMD part's TDP is not recorded.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon R5 M255 has an average benchmark score of 4788, compared to the NVIDIA GeForce GT 745M's 3953. The AMD part also sits in the 28th percentile of all GPUs, versus the 23rd percentile for the NVIDIA part.

Q: How do the two GPUs compare in Vulkan performance?

A: The NVIDIA GeForce GT 745M leads in the Geekbench Vulkan test with a score of 5502, while the AMD Radeon R5 M255 scores 4925. That is an 11.7% advantage for NVIDIA.

Q: Which GPU is better for OpenCL compute workloads?

A: The AMD Radeon R5 M255 is substantially better in OpenCL. It scores 4650 in Geekbench OpenCL, which is 23% higher than the GeForce GT 745M's 3580.

Q: What are the memory bandwidth differences?

A: The NVIDIA GT 745M uses GDDR5 memory with a bandwidth of 64.00 GB/s. The AMD R5 M255 uses DDR3 memory with a bandwidth of 32.00 GB/s, exactly half of NVIDIA's.

Q: Do the two GPUs have the same number of shading units?

A: Yes, both have 384 shading units. However, the AMD part has 24 TMUs and 8 ROPs, while the NVIDIA part has 32 TMUs and 16 ROPs.

Q: Which GPU was released later?

A: The AMD Radeon R5 M255 was released on 2014-10-11, while the NVIDIA GeForce GT 745M was released earlier on 2013-03-31.

The Verdict

The performance split is clear from the recorded benchmark data. For users who prioritize OpenCL compute, the AMD Radeon R5 M255 is the superior choice. Its 23% lead in Geekbench OpenCL, combined with higher FP32 throughput (721.9 GFLOPS versus 421.6 GFLOPS), makes it the stronger compute engine. The higher average benchmark score of 4788 reinforces this.

For users who prioritize Vulkan performance, the NVIDIA GeForce GT 745M is the better pick. Its Geekbench Vulkan score of 5502 beats the AMD part by 11.7%, and it does so despite lower raw specifications. This indicates better Vulkan efficiency or driver maturity, which matters for modern gaming and compute applications.

The AMD part offers advantages in texture and pixel rates (22.56 GTexel/s and 7.520 GPixel/s versus 17.57 GTexel/s and 4.392 GPixel/s) and supports DirectX 12 (12_0) versus NVIDIA's 12 (11_0). The NVIDIA part counters with double the memory bandwidth (64.00 GB/s versus 32.00 GB/s) and a wider PCIe interface (x16 versus x8).

There is no overall winner in the data. The choice depends entirely on the target workload. OpenCL-centric users should pick the Radeon R5 M255. Vulkan-centric users should pick the GeForce GT 745M. For mixed workloads, the average scores suggest AMD has a slight edge, but the magnitude of the Vulkan win for NVIDIA means that any Vulkan usage tips the balance back toward the GT 745M. Both are end-of-life parts, so the decision is relevant only for legacy systems or low-cost replacements. The recorded data does not show one GPU outperforming the other across the board; it shows two specialists in different APIs.