Best CPU for the RTX 4090
The NVIDIA GeForce RTX 4090 has a 1440p performance index of 82/100. To keep it busy a processor needs a gaming index of roughly 89 at 1440p and 96 at 1080p; anything above that is headroom, anything far above is money better spent on the graphics card. Below: the processors that hit the sweet spot, then the cheapest safe pick on each socket.
Sweet-spot processors (1440p)
| # | CPU | Socket | 1080p | 1440p | 4K |
|---|---|---|---|---|---|
| 1 | Ryzen 9 7950X3D | AM5 | CPU 5% | GPU 2% | GPU 22% |
| 2 | Core i9-14900K | LGA1700 | CPU 9% | CPU 2% | GPU 18% |
| 3 | Ryzen 7 7800X3D | AM5 | CPU 4% | GPU 3% | GPU 23% |
| 4 | Core i7-14700K | LGA1700 | CPU 10% | CPU 4% | GPU 17% |
| 5 | Ryzen 9 9950X | AM5 | CPU 10% | CPU 4% | GPU 17% |
| 6 | Core i9-13900K | LGA1700 | CPU 11% | CPU 5% | GPU 16% |
| 7 | Core Ultra 9 285K | LGA1851 | CPU 12% | CPU 6% | GPU 15% |
| 8 | Ryzen 9 9900X | AM5 | CPU 12% | CPU 6% | GPU 15% |
| 9 | Core i7-13700K | LGA1700 | CPU 13% | CPU 7% | GPU 14% |
| 10 | Ryzen 9 7950X | AM5 | CPU 13% | CPU 7% | GPU 14% |
Cheapest processor that avoids a bottleneck, per socket
- AM5: Ryzen 9 7900X (gaming index 81, 12 cores)
- LGA1700: Core i7-13700K (gaming index 83, 16 cores)
- LGA1851: Core Ultra 9 285K (gaming index 84, 24 cores)
If you already own a motherboard, start from its socket. AM4 and LGA1700 are end-of-line but cheap; AM5 and LGA1851 leave an upgrade path for the next GPU.
Processors to avoid with this card
These would leave the RTX 4090 waiting: Ryzen 5 3600 (46% CPU bottleneck at 1440p), Core i5-10400F (44% CPU bottleneck at 1440p), Ryzen 7 3700X (42% CPU bottleneck at 1440p), Ryzen 5 5500 (42% CPU bottleneck at 1440p), Core i5-11400F (37% CPU bottleneck at 1440p).