AMD Radeon R7 Graphics vs NVIDIA GeForce GT 645M Comparison

FAQ

Q: Which GPU is faster in the database's recorded benchmarks?

A: The AMD Radeon R7 Graphics wins both head-to-head tests. It scores 4015 in Geekbench OpenCL versus 2680 for the NVIDIA GeForce GT 645M, a 49.8% advantage, and 5980 in Geekbench Vulkan versus 4875, a 22.7% lead.

Q: How do these two GPUs rank against all GPUs in the database?

A: The AMD Radeon R7 Graphics sits at the 29th percentile, while the NVIDIA GeForce GT 645M sits at the 26th percentile. The AMD part also has a higher average benchmark score: 4998 versus 4411.

Q: What are the closest rivals to the AMD Radeon R7 Graphics?

A: The nearest rivals include the NVIDIA Quadro 4000 (average score 4979, only 0.4% behind), the AMD Radeon R5 M430 (5018, 0.4% ahead), the NVIDIA GeForce RTX 5060 Ti 16 GB (4970, 0.6% behind), and the AMD FirePro W4170M (5034, 0.7% ahead).

Q: What are the closest rivals to the NVIDIA GeForce GT 645M?

A: The nearest rivals include the NVIDIA GeForce 930M (4388, 0.5% behind), the Intel Iris Pro Graphics 5200 (4360, 1.2% behind), the NVIDIA GeForce RTX 4070 GDDR6 (4335, 1.8% behind), and the AMD Radeon R7 M260 (4499, 1.9% ahead).

Q: Which GPU has the higher pixel and texture rates?

A: The NVIDIA GeForce GT 645M has the higher pixel rate at 6.240 GPixel/s versus 5.760 GPixel/s for the AMD part. It also has a higher texture rate at 24.96 GTexel/s versus 17.28 GTexel/s.

Q: Do both GPUs support DirectX 12?

A: Both support DirectX 12, but at different feature levels. The AMD Radeon R7 Graphics supports DirectX 12 (12_0), while the NVIDIA GeForce GT 645M supports DirectX 12 (11_0).

Architecture Differences

The AMD Radeon R7 Graphics is an integrated graphics processor built on the GCN 2.0 architecture, part of the GCN 2.0 IGP generation under the Kaveri family. Its chip is codenamed Spectre Lite and is manufactured on a 28 nm process at GlobalFoundries. The die contains 2,410 million transistors across a 245 mm² area, giving a transistor density of 9.8M per mm². This is an IGP with no dedicated memory; it uses system shared memory, and its bandwidth is system dependent.

The NVIDIA GeForce GT 645M uses the Kepler architecture and belongs to the GeForce 600M generation. Its chip is the GK107, also on a 28 nm process but fabricated by TSMC. The die is smaller at 118 mm² with 1,270 million transistors, yielding a higher transistor density of 10.8M per mm². Unlike the AMD part, the GT 645M has dedicated 2 GB of DDR3 memory on a 128-bit bus, with 28.80 GB/s of bandwidth. It connects via PCIe 3.0 x16 rather than an IGP interface.

The two GPUs share the same shading unit count at 384, but the NVIDIA part has more texture mapping units (32 versus 24) and more render output units (16 versus 8). This structural difference explains why the GT 645M achieves higher pixel and texture rates despite similar FP32 throughput. The AMD part delivers 553.0 GFLOPS of FP32 compute, while the NVIDIA part delivers 599.0 GFLOPS, a modest edge for the discrete GPU.

The AMD Radeon R7 Graphics supports DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170. The NVIDIA GeForce GT 645M supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175. Both are end-of-life products, but the AMD part was released later and lists its predecessor as TeraScale 3 IGP and successor as GCN 3.0 IGP. The NVIDIA part lists its predecessor as GeForce 500M and successor as GeForce 700M.

The power profiles differ notably. The AMD IGP has a TDP of 25 W, while the NVIDIA discrete GPU has a TDP of 32 W. The AMD part has no power connectors as an IGP, while the NVIDIA part also lists none, which is typical for a mobile GPU. Display outputs are motherboard dependent for the AMD part and portable device dependent for the NVIDIA part.

Head-to-Head Benchmarks

The recorded head-to-head data covers two workloads: Geekbench OpenCL and Geekbench Vulkan. The AMD Radeon R7 Graphics wins both, but the margin tells an interesting story about where each architecture excels.

In Geekbench OpenCL, the AMD Radeon R7 Graphics scores 4015 against 2680 for the NVIDIA GeForce GT 645M. That is a 49.8% advantage, the largest gap in either test. OpenCL compute workloads tend to favor the AMD architecture here, and the integrated part's GCN 2.0 design appears to handle these tasks substantially better than the Kepler-based GT 645M. The NVIDIA part still has a higher theoretical FP32 rate at 599.0 GFLOPS versus 553.0 GFLOPS, yet it trails badly in the actual OpenCL result, suggesting that raw FLOPs do not translate directly into benchmark performance in this comparison.

In Geekbench Vulkan, the AMD part scores 5980 against 4875 for the NVIDIA part, a 22.7% lead. The gap narrows considerably compared to OpenCL, which indicates that the NVIDIA GPU is relatively stronger in Vulkan workloads. Still, the AMD Radeon R7 Graphics maintains a clear win. Interestingly, the AMD part's Vulkan score of 5980 is much higher than its OpenCL score of 4015, while the NVIDIA part shows a smaller gap between its Vulkan score of 4875 and its OpenCL score of 2680. This suggests the AMD architecture scales better into Vulkan, while the NVIDIA part has a more balanced but lower overall profile.

The average benchmark score reinforces the AMD advantage. The Radeon R7 Graphics averages 4998 across its benchmarks, while the GT 645M averages 4411. That difference of roughly 587 points places them in different performance tiers in the database, even though both are near the bottom of the overall GPU distribution, at the 29th and 26th percentiles respectively.

Specification Differences

The two GPUs differ across nearly every major specification category, though they share some common ground.

Process node: both are 28 nm, but the AMD part is made by GlobalFoundries while the NVIDIA part is made by TSMC.

Die and transistors: the AMD Spectre Lite die is 245 mm² with 2,410 million transistors, while the NVIDIA GK107 die is 118 mm² with 1,270 million transistors. The AMD part is larger in both absolute die size and transistor count, but the NVIDIA part has a higher transistor density at 10.8M per mm² versus 9.8M per mm².

Memory: the AMD Radeon R7 Graphics uses system shared memory with system dependent bandwidth, while the NVIDIA GeForce GT 645M has 2 GB of DDR3 on a 128-bit bus with 28.80 GB/s of bandwidth. The memory clock for the NVIDIA part is listed at 900 MHz with 1800 Mbps effective, while the AMD part lists its memory clock as system shared.

Core configuration: both have 384 shading units, but the NVIDIA part has 32 TMUs versus 24, and 16 ROPs versus 8.

Rates: the NVIDIA part has a higher pixel rate at 6.240 GPixel/s versus 5.760 GPixel/s, and a higher texture rate at 24.96 GTexel/s versus 17.28 GTexel/s. FP32 is also higher on the NVIDIA part at 599.0 GFLOPS versus 553.0 GFLOPS.

Clocks: the NVIDIA part has a base clock of 709 MHz and a boost clock of 780 MHz, while the AMD part lists no base or boost clock values. This reflects its nature as an integrated GPU whose clocks are tied to the host system.

TDP: the AMD part is rated at 25 W, the NVIDIA part at 32 W.

Bus interface: the AMD part is IGP, while the NVIDIA part uses PCIe 3.0 x16.

API support: both support OpenGL 4.6 and Vulkan, but the AMD part supports DirectX 12 (12_0) while the NVIDIA part supports DirectX 12 (11_0). The Vulkan versions differ slightly, 1.2.170 for AMD and 1.2.175 for NVIDIA.

Release dates: the AMD Radeon R7 Graphics was released later, while the NVIDIA GeForce GT 645M came earlier. Both are end-of-life.

The Verdict

The data is unambiguous: the AMD Radeon R7 Graphics is the faster GPU in every recorded benchmark. It wins Geekbench OpenCL by 49.8% and Geekbench Vulkan by 22.7%, and it holds a higher average benchmark score of 4998 versus 4411. Its percentile ranking is also higher at 29 versus 26.

The NVIDIA GeForce GT 645M does have advantages in raw specification counts. It has more TMUs, more ROPs, higher pixel and texture rates, higher FP32 throughput, and dedicated memory with a 128-bit bus and 28.80 GB/s of bandwidth. Yet none of these translate into a benchmark win in the recorded data. The AMD part, despite being an IGP with system shared memory, dominates both compute workloads.

The closest rival comparisons reinforce the positioning. The AMD Radeon R7 Graphics sits within a tight cluster of GPUs averaging around 4970 to 5034, with deltas under 1% in either direction. The NVIDIA GeForce GT 645M sits in a similar cluster around 4335 to 4499, but that cluster is roughly 500 to 600 points lower. In other words, the two GPUs are not really competing in the same tier according to the database; the AMD part lands a full performance class higher.

For buyers or system builders choosing between these two, the AMD Radeon R7 Graphics is the stronger pick for general compute and Vulkan workloads. The NVIDIA GeForce GT 645M might still be considered for scenarios where its dedicated memory helps, such as texture-heavy applications, but the benchmark data does not provide evidence of that advantage. The recorded scores favor AMD across the board.

Where Each One Wins

The AMD Radeon R7 Graphics wins in OpenCL compute by a wide margin. Its score of 4015 versus 2680 represents a 49.8% lead, the largest gap in the head-to-head data. It also wins in Vulkan, scoring 5980 versus 4875, a 22.7% advantage. The AMD part has the higher average benchmark score at 4998 and the higher percentile ranking at 29.

The NVIDIA GeForce GT 645M wins in several specification-level categories. It has a higher pixel rate at 6.240 GPixel/s versus 5.760 GPixel/s, a higher texture rate at 24.96 GTexel/s versus 17.28 GTexel/s, and higher FP32 throughput at 599.0 GFLOPS versus 553.0 GFLOPS. It also has twice the ROP count at 16 versus 8, more TMUs at 32 versus 24, and dedicated 2 GB of DDR3 memory with 28.80 GB/s of bandwidth. Its transistor density is higher at 10.8M per mm² versus 9.8M per mm², and it supports a slightly newer Vulkan version at 1.2.175 versus 1.2.170.

The use-case split is therefore clear. For compute-oriented tasks measured by OpenCL and Vulkan, the AMD Radeon R7 Graphics is the stronger performer. For tasks that rely on fill rates, memory bandwidth, or the presence of dedicated VRAM, the NVIDIA GeForce GT 645M has the specification-level advantages, though the database contains no benchmark that directly demonstrates a win for the NVIDIA part. The recorded data shows AMD winning both head-to-head tests, which makes the GT 645M a harder recommendation despite its higher theoretical rates.