PCPairs

Core i5-12400F + RTX 4080: bottleneck check

15%

CPU-limited at 1440p. Mild CPU bottleneck.

The Core i5-12400F cannot feed the RTX 4080 fast enough at 1440p, so the card sits partly idle in CPU-heavy games.

By resolution

ResolutionLimiting partSeverityVerdict
1080pCPU 21%mild CPU bottleneck
1440pCPU 15%mild CPU bottleneck
4KGPU 8%balanced

This is the classic pattern: at 1080p the Core i5-12400F is the limit (21%), while at 4K the RTX 4080 takes over (8% GPU-limited). If you play at 1080p on a high-refresh monitor, a faster CPU is the upgrade that matters; at 1440p or 4K this pair is already well matched.

Specifications

Intel Core i5-12400F
Cores / threads6 / 12
Max boost4.4 GHz
SocketLGA1700
Maximum turbo power (MTP)117 W Intel's published maximum sustained turbo power, above its base power; the PSU estimate uses it, so it errs high · Intel ARK
Released2022
Gaming index66 / 100
Multi-core index48 / 100
NVIDIA GeForce RTX 4080
VRAM16 GB
Board power320 W
Released2022
1080p index66.6 / 100
1440p index62 / 100
4K index57.7 / 100

Power supply

The RTX 4080 measured 304 W average while gaming (371 W highest 20 ms spike, TechPowerUp). With the Core i5-12400F at its maximum turbo power of 117 W and about 75 W for the rest of the system, the sustained load is about 496 W. A 750 W unit is the safe choice; a good-quality 650 W unit also covers the measured draw. Details on the RTX 4080 PSU page or try other pairs in the PSU calculator.

Upgrade paths

Best CPU for the RTX 4080 Best GPU for the Core i5-12400F RTX 4080 PSU requirements

Indexes are relative estimates aggregated from published reviews; real results vary by game, settings, memory speed and drivers. Methodology.