Radeon RX 7900 XTX vs GeForce GT 645 OEM
Primary details
GPU architecture, market segment, value for money and other general parameters compared.
| Place in the ranking | not rated | 8 |
| Place by popularity | not in top-100 | 70 |
| Cost-effectiveness evaluation | no data | 34.71 |
| Power efficiency | no data | 15.57 |
| Architecture | Fermi 2.0 (2010−2014) | RDNA 3.0 (2022−2024) |
| GPU code name | GF114 | Navi 31 |
| Market segment | Desktop | Desktop |
| Release date | 24 April 2012 (12 years ago) | 3 November 2022 (2 years ago) |
| Launch price (MSRP) | no data | $999 |
Cost-effectiveness evaluation
Performance to price ratio. The higher, the better.
Detailed specifications
General parameters such as number of shaders, GPU core base clock and boost clock speeds, manufacturing process, texturing and calculation speed. Note that power consumption of some graphics cards can well exceed their nominal TDP, especially when overclocked.
| Pipelines / CUDA cores | 288 | 6144 |
| Core clock speed | 776 MHz | 1929 MHz |
| Boost clock speed | no data | 2498 MHz |
| Number of transistors | 1,950 million | 57,700 million |
| Manufacturing process technology | 40 nm | 5 nm |
| Power consumption (TDP) | 102 Watt | 355 Watt |
| Texture fill rate | 37.25 | 959.2 |
| Floating-point processing power | 0.894 TFLOPS | 61.39 TFLOPS |
| ROPs | 24 | 192 |
| TMUs | 48 | 384 |
| Ray Tracing Cores | no data | 96 |
Form factor & compatibility
Information on compatibility with other computer components. Useful when choosing a future computer configuration or upgrading an existing one. For desktop graphics cards it's interface and bus (motherboard compatibility), additional power connectors (power supply compatibility).
| Interface | PCIe 2.0 x16 | PCIe 4.0 x16 |
| Length | 210 mm | 287 mm |
| Width | 2-slot | 2-slot |
| Supplementary power connectors | no data | 2x 8-pin |
VRAM capacity and type
Parameters of VRAM installed: its type, size, bus, clock and resulting bandwidth. Integrated GPUs have no dedicated video RAM and use a shared part of system RAM.
| Memory type | GDDR5 | GDDR6 |
| Maximum RAM amount | 1 GB | 24 GB |
| Memory bus width | 192 Bit | 384 Bit |
| Memory clock speed | 957 MHz | 2500 MHz |
| Memory bandwidth | 91.87 GB/s | 960.0 GB/s |
| Shared memory | - | - |
Connectivity and outputs
Types and number of video connectors present on the reviewed GPUs. As a rule, data in this section is precise only for desktop reference ones (so-called Founders Edition for NVIDIA chips). OEM manufacturers may change the number and type of output ports, while for notebook cards availability of certain video outputs ports depends on the laptop model rather than on the card itself.
| Display Connectors | 2x DVI, 1x mini-HDMI | 1x HDMI 2.1a, 2x DisplayPort 2.1, 1x USB Type-C |
| HDMI | + | + |
API compatibility
List of supported 3D and general-purpose computing APIs, including their specific versions.
| DirectX | 12 (11_0) | 12 Ultimate (12_2) |
| Shader Model | 5.1 | 6.7 |
| OpenGL | 4.6 | 4.6 |
| OpenCL | 1.1 | 2.2 |
| Vulkan | N/A | 1.3 |
| CUDA | 2.1 | - |
Pros & cons summary
| Recency | 24 April 2012 | 3 November 2022 |
| Maximum RAM amount | 1 GB | 24 GB |
| Chip lithography | 40 nm | 5 nm |
| Power consumption (TDP) | 102 Watt | 355 Watt |
GT 645 OEM has 248% lower power consumption.
RX 7900 XTX, on the other hand, has an age advantage of 10 years, a 2300% higher maximum VRAM amount, and a 700% more advanced lithography process.
We couldn't decide between GeForce GT 645 OEM and Radeon RX 7900 XTX. We've got no test results to judge.
Should you still have questions concerning choice between the reviewed GPUs, ask them in Comments section, and we shall answer.
Comparisons with similar GPUs
We selected several comparisons of graphics cards with performance close to those reviewed, providing you with more options to consider.
