Introduction and parameters
A major drawback of the exceptionally powerful GeForce RTX 5090 is the high power demands of its large GB202 chip. Even when equipped with a premium air cooler, the card still requires robust system cooling to handle its nearly 600W heat output. However, AiO liquid cooling models can offer even better thermal performance, thanks to their larger radiators with three 120mm fans, which expel hot air directly outside the case.
The RTX 5090 occupies a unique market position – a consequence of its significant performance lead over competing cards. Like its predecessors (RTX 4090, RTX 3090 Ti and Titan series), it straddles the line between enthusiast gaming and professional workloads. While featuring some limitations compared to pure workstation cards (most notably the 32GB memory capacity), it remains substantially more affordable. For pure gaming, the RTX 5090 represents expensive overkill, but for professional use it offers a cost-effective alternative to RTX Pro Blackwell cards.
Having already reviewed the GeForce RTX 5090, let’s recap its key specifications: The card features Blackwell 2.0 architecture manufactured on TSMC’s 4nm process, packing 21,760 CUDA cores, 680 texture units and 192 raster operations units. Its 32GB GDDR7 memory on a 512-bit bus delivers 1.79TB/s bandwidth. Base clock operates at 2017MHz with boost up to 2407MHz. The card supports DirectX 12 Ultimate with dedicated ray tracing and AI acceleration, while its power limit is set at 575W.
A more detailed parameter comparison with the closest models is shown in the following table.
| GeForce RTX 5090 | GeForce RTX 5080 | GeForce RTX 4090 | GeForce RTX 4080 Super | GeForce RTX 4080 | |
| Shader cores | Blackwell | Blackwell | Ada Lovelace | Ada Lovelace | Ada Lovelace |
| Nvidia CUDA cores (SP) | 21760 | 10752 | 16384 | 10240 | 9728 |
| Texture Mapping Units | 680 | 336 | 512 | 320 | 304 |
| Render Output Units | 176 | 128 | 176 | 112 | 112 |
| RT cores | 318 TFLOPS | 171 TFLOPS | 191 TFLOPS | 121 TFLOPS | 113 TFLOPS |
| Tensor Cores | 3352 AI TOPS | 1801 AI TOPS | 1321 AI TOPS | 836 AI TOPS | 780 AI TOPS |
| Boost Clock | 2.41 GHz | 2.62 GHz | 2.52 GHz | 2.55 GHz | 2.51 GHz |
| Base Clock | 2.10 GHz | 2.30 GHz | 2.23 GHz | 2.29 GHz | 2.21 GHz |
| Memory | 32 GB GDDR7 | 16 GB DDR7 | 24 GB GDDR6X | 16 GB GDDR6X | 16 GB GDDR6X |
| Memory Bus Width | 512-bit | 256-bit | 384-bit | 256-bit | 256-bit |
| Memory Bandwidth | 1792 GB/s | 960 GB/s | 1008 GB/s | 736 GB/s | 717 GB/s |
| Max. resolution | 4K at 480Hz or 8K at 120Hz with DSC | 4K at 480Hz or 8K at 120Hz with DSC | 4K at 240 Hz or 8K at 60 Hz with DSC, HDR | 4K at 240 Hz or 8K at 60 Hz with DSC, HDR | 4K at 240 Hz or 8K at 60 Hz with DSC, HDR |
| Standard Display Connectors | 3× DisplayPort, 1× HDMI | 3× DisplayPort, 1× HDMI | 3× DisplayPort, 1× HDMI | 3× DisplayPort, 1× HDMI | 3× DisplayPort, 1× HDMI |
| PCI Express | Gen 5 | Gen 5 | Gen 4 | Gen 4 | Gen 4 |
| Nvidia Encoder | 3× 9th gen | 2× 9th gen | 2× 8th gen | 2× 8th gen | 2× 8th gen |
| Nvidia Decoder | 2× 6th gen | 2× 6th gen | 1× 5th gen | 1× 5th gen | 1× 5th gen |
| length | 304 mm | 304 mm | 304 mm | 304 mm | 304 mm |
| width | 137 mm | 137 mm | 137 mm | 137 mm | 137 mm |
| height | 2-slot | 2-slot | 3-slot | 3-slot | 3-slot |
| Total Graphics Power | 575 W | 360 W | 450 W | 320 W | 320 W |
| Supplementary Power Connectores | 4× 8pin PCIe (adapter) or 1× 600 W PCIe Gen 5 | 3× 8pin PCIe (adapter) or 1× 450 W PCIe Gen 5 | 3× 8pin PCIe (adapter) or 1× 450 W PCIe Gen 5 | 3× 8pin PCIe (adapter) or 1× 450 W PCIe Gen 5 | 3× 8pin PCIe (adapter) or 1× 450 W PCIe Gen 5 |
Today we’re examining Asus’ flagship ROG Astral LC GeForce RTX 5090 32GB GDDR7 OC Edition, featuring factory overclocking and an extreme AiO cooler with triple 120mm fans.
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The card comes factory overclocked. The power limit has been increased to 600 W, which is the maximum allowed by the 16-pin 12V-2×6 auxiliary power connector according to specifications. The reported typical boost clock has been raised from the reference 2407 MHz to 2560 MHz (with the option to activate OC mode at 2610 MHz in GPU Tweak III).
The card also features a dual BIOS. The reported clock speeds don’t differ between them – the difference lies solely in the cooling regulation settings. In the performance-oriented mode, the fans run at higher RPMs at the same temperatures, making the card slightly cooler and achieving marginally higher real-world clock speeds. Detailed tests of operating characteristics in the relevant chapters will show how the card’s behavior differs in terms of both fan performance and clock speeds.
The parameters of both BIOS versions, as read by GPU-Z, are shown in the screenshots below. We’ll be testing with the quieter BIOS, as the performance difference is minimal, but the same can’t be said for noise levels./p>
Primary BIOS (performance)
Secondary BIOS (quiet)
GPU-Z can only read basic monitoring values, while HWiNFO can monitor more. What HWiNFO could monitor on the card during testing is visible in the screenshot below. In a newer beta version released after I returned the card, support was added for monitoring currents on individual pins of the 12V-2×6 connector, which is a specialty of more expensive Astral models from Asus.
The back of the packaging highlights the key technologies used in the card, with a particular focus on its AiO cooling solution. The cooler is divided into two parts: a water block that cools the GPU and memory, and a large metal heatsink with its own fan for cooling the card’s other components. Heat is carried away to a tall 360mm radiator equipped with three 120mm fans. Instead of traditional thermal paste, the GPU uses a special thermal pad for better conductivity. The card also features a reinforced power delivery system compared to the reference design. For overclocking and monitoring, Asus provides its GPU Tweak III software. Additionally, the card offers expanded display outputs, including a second HDMI port not found on standard models.
The packaging has the width and height of regular boxes, but the depth is about three times greater. When unpacking, you need to peel off the outer printed cardboard. Inside is a box with a flip-top lid containing rigid foam inserts. In the upper part is the card itself, below it is the water cooling radiator and accessories.
With the card you also get some extra small items. They’re nice to have, but essentially don’t differ from what you get with cheaper card models from Asus ROG premium lines.
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