AMD Radeon R5 Graphics vs NVIDIA GeForce GT 640 Comparison

AMD Radeon R5 Graphics and NVIDIA GeForce GT 640 represent two very different approaches to graphics processing, with the former being an integrated processor and the latter a dedicated add-in board. The benchmark data shows a split decision: each part wins one of the two recorded head-to-head tests. The AMD Radeon R5 Graphics takes the OpenCL test handily, while the NVIDIA GeForce GT 640 counters with a decisive victory in the Vulkan test. The average benchmark scores, however, tell a more nuanced story about overall performance distribution.

Where Each One Wins

The AMD Radeon R5 Graphics is the clear winner in the OpenCL workload. The recorded data shows a score of 5183 against the GeForce GT 640's 3736, a delta of 38.7% in favor of the AMD part. This is a substantial lead, indicating that the Radeon R5's architecture handles the general-purpose compute tasks measured by OpenCL with significantly greater efficiency. For workloads that leverage this API, such as certain content creation or compute acceleration tasks, the Radeon R5 Graphics provides a measurable advantage.

The NVIDIA GeForce GT 640, conversely, dominates in the Vulkan graphics API test. Its score of 3809 eclipses the Radeon R5's 2582, a 32.2% margin in the opposite direction. Vulkan is a modern, low-overhead graphics API, and the GT 640's architecture, while older, clearly has strengths in this specific environment. For gaming or applications that utilize Vulkan, the GeForce GT 640 is the more capable performer.

The database's average benchmark score, which aggregates results across multiple tests, shows the AMD Radeon R5 Graphics at 3883, placing it in the 23rd percentile of all GPUs. The NVIDIA GeForce GT 640 has a lower average score of 3210, placing it in the 20th percentile. This suggests that the Radeon R5's strong OpenCL result lifts its overall standing, despite the GeForce GT 640's superior Vulkan performance. The win count is even, at one victory apiece, but the magnitude of the Radeon R5's OpenCL win is larger than the GeForce GT 640's Vulkan win.

Architecture Differences

The two products are built on fundamentally different designs. The AMD Radeon R5 Graphics is an integrated graphics processor (IGP) based on the GCN 2.0 architecture, with the chip codename "Spectre SL" and a generation identified as "GCN 2.0 IGP (Kaveri)." This places it within AMD's Kaveri family of accelerated processing units. The NVIDIA GeForce GT 640 is a dedicated graphics card using the Kepler architecture, with the chip codename "GK107," and belongs to the GeForce 600 generation.

Fabrication processes are similar, both at 28 nm, but the foundries differ. The Radeon R5 is produced by GlobalFoundries, while the GeForce GT 640 is built by TSMC. The transistor counts show a significant divergence: the AMD chip packs 2,410 million transistors on a 245 mm² die, resulting in a density of 9.8 million transistors per square millimeter. The NVIDIA chip is smaller and leaner, with 1,270 million transistors on a 118 mm² die, but achieves a higher density of 10.8 million transistors per square millimeter.

Memory architecture is starkly different. The Radeon R5 uses "System Shared" memory, meaning it relies on the host system's RAM for both capacity and bandwidth, with the bus width also being system-dependent. The GeForce GT 640, in contrast, has dedicated memory: 2 GB of DDR3 on a 128-bit bus, providing a fixed bandwidth of 28.51 GB/s. This fundamental difference affects how each card handles memory-intensive tasks.

Feature support also diverges. The Radeon R5 supports DirectX 12 (12_0), OpenGL 4.6, and Vulkan 1.2.170. The GeForce GT 640 supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175. While both support the same OpenGL version, the DirectX feature levels differ, and the NVIDIA part has a slightly newer Vulkan revision. The Radeon R5's interface is "IGP," meaning it connects through the motherboard, while the GeForce GT 640 uses a PCIe 3.0 x16 interface.

FAQ

Q: Which GPU has a higher average benchmark score?

A: The AMD Radeon R5 Graphics has a higher average benchmark score of 3883, compared to the NVIDIA GeForce GT 640's 3210.

Q: What is the difference in OpenCL performance between the two?

A: The AMD Radeon R5 Graphics scores 5183 in OpenCL, which is 38.7% higher than the NVIDIA GeForce GT 640's score of 3736.

Q: Which GPU has the advantage in Vulkan performance?

A: The NVIDIA GeForce GT 640 wins in Vulkan, with a score of 3809 versus the AMD Radeon R5 Graphics' 2582, a difference of 32.2%.

Q: How do their memory configurations differ?

A: The AMD Radeon R5 Graphics uses system-shared memory with system-dependent size, type, bus width, and bandwidth. The NVIDIA GeForce GT 640 has dedicated 2 GB of DDR3 memory on a 128-bit bus with a bandwidth of 28.51 GB/s.

Q: What are the transistor counts for these chips?

A: The AMD Radeon R5 Graphics has 2,410 million transistors, while the NVIDIA GeForce GT 640 has 1,270 million transistors.

Q: Which GPU has a higher pixel fill rate?

A: The NVIDIA GeForce GT 640 has a higher pixel rate of 7.216 GPixel/s, compared to the AMD Radeon R5 Graphics' 3.032 GPixel/s.

Specification Differences

The two graphics solutions diverge across nearly every specification category. The AMD Radeon R5 Graphics is an IGP based on GCN 2.0, while the NVIDIA GeForce GT 640 is a dedicated card with the Kepler architecture. The Radeon R5 uses a 28 nm process from GlobalFoundries and contains 2,410 million transistors on a 245 mm² die. The GeForce GT 640 also uses 28 nm, but from TSMC, with 1,270 million transistors on a smaller 118 mm² die, leading to a higher transistor density of 10.8M per mm² versus the AMD's 9.8M per mm².

The execution resources differ considerably. The Radeon R5 has 256 shading units, 16 texture mapping units, and 4 ROPs. The GeForce GT 640 has 384 shading units, 32 TMUs, and 16 ROPs. The NVIDIA part's higher counts translate into higher theoretical rates: its pixel rate is 7.216 GPixel/s and texture rate is 28.86 GTexel/s, while the Radeon R5 posts 3.032 GPixel/s and 12.13 GTexel/s respectively. The FP32 performance also favors NVIDIA, at 692.7 GFLOPS versus the AMD's 388.1 GFLOPS.

Memory is another major differentiator. The Radeon R5 uses system-shared memory, with no dedicated VRAM, bus width, or fixed bandwidth. The GeForce GT 640 has 2 GB of DDR3 memory on a 128-bit bus with a bandwidth of 28.51 GB/s. The TDP reflects the integration status: the Radeon R5 is rated at 15 W, while the GeForce GT 640 draws 65 W and has a suggested PSU of 250 W. The NVIDIA card is a single-slot design with no power connectors, measuring 145 mm in length, whereas the AMD IGP has no physical dimensions as it is integrated into the motherboard.

The GeForce GT 640 also offers a set of display outputs including 1x DVI, 1x HDMI 1.4a, and 1x DisplayPort 1.2, while the Radeon R5's outputs are motherboard-dependent. The bus interface is PCIe 3.0 x16 for the NVIDIA card, versus IGP for the AMD. Their release dates are about two years apart, with the GeForce GT 640 launching in June 2012 and the Radeon R5 Graphics in September 2014. Both are now listed as end-of-life products.

Head-to-Head Benchmarks

The most decisive result in the recorded data is the OpenCL test, where the AMD Radeon R5 Graphics scores 5183 against the NVIDIA GeForce GT 640's 3736. This 38.7% delta is the largest performance gap between the two in any benchmark. The Radeon R5's advantage in this compute-oriented test is significant and suggests that its GCN 2.0 architecture is particularly well-suited to the parallel workloads that OpenCL measures. This single result is large enough to push the Radeon R5's average benchmark score to 3883, which is higher than the GeForce GT 640's 3210 average, despite the NVIDIA part's better showing in the other test.

The Vulkan test flips the result decisively in favor of the NVIDIA GeForce GT 640. Here, the GT 640 scores 3809, while the Radeon R5 Graphics manages only 2582. The 32.2% margin for the NVIDIA part is substantial, demonstrating a clear architectural strength in handling this API's lower-level, more efficient graphics pipeline. This victory highlights that the GT 640, despite its lower average score and older release date, retains a competitive edge in modern graphics workloads.

When viewed against their respective nearest rivals, both parts occupy similar performance tiers. The AMD Radeon R5 Graphics sits between the NVIDIA Quadro 2000 (3898, a 0.4% difference) and the NVIDIA GeForce MX110 (3834, a 1.3% difference). The NVIDIA GeForce GT 640, meanwhile, is near the Intel Arc Pro B60 (3182, a 0.9% difference) and the NVIDIA Quadro P1000 (3163, a 1.5% difference). The data indicates that the Radeon R5's average score places it slightly above the GeForce GT 640's average, but both are within a narrow performance band. The GeForce GT 640's Vulkan win, however, proves that its architecture has specific strengths that the average score does not fully capture. The Radeon R5's OpenCL dominance, conversely, is a clear signal that for compute workloads, it is the better choice. Each part wins where its design excels, making the selection dependent on the primary application's API preferences.