Will the Core i5-10400F bottleneck the RTX 3090?

Yes, at 1440p the Core i5-10400F is estimated to limit the RTX 3090 by about 26%. The effect is larger at 1080p and smaller at 4K.

What power supply do I need for a Core i5-10400F and RTX 3090?

Estimated system load is about 515 W. A quality 750 W unit leaves roughly 30% headroom for transient spikes.

Is this pair better at 1080p or 4K?

1080p: CPU-limited 32% (moderate CPU bottleneck). 1440p: CPU-limited 26% (moderate CPU bottleneck). 4K: CPU-limited 6% (balanced).

PCPairs

Core i5-10400F + RTX 3090: bottleneck check

26%

CPU-limited at 1440p. Moderate CPU bottleneck.

CPU GPU

The Core i5-10400F cannot feed the RTX 3090 fast enough at 1440p, so the card sits partly idle in CPU-heavy games.

By resolution

Resolution	Limiting part	Severity	Verdict
1080p	CPU	32%	moderate CPU bottleneck
1440p	CPU	26%	moderate CPU bottleneck
4K	CPU	6%	balanced

The Core i5-10400F is the limiting part at every resolution, even at 4K (6%). The RTX 3090 is a much stronger card than this processor can drive — plan a CPU upgrade before spending more on graphics.

Specifications

Intel Core i5-10400F
Cores / threads	6 / 12
Max boost	4.3 GHz
Socket	LGA1200
Max turbo power	65 W
Released	2020
Gaming index	50 / 100
Multi-core index	38 / 100

NVIDIA GeForce RTX 3090
VRAM	24 GB
Board power	350 W
Released	2020
1080p index	51.7 / 100
1440p index	46 / 100
4K index	40.9 / 100

Power supply

CPU 65 W + GPU 350 W + about 100 W for motherboard, memory, storage and fans gives an estimated peak load of 515 W. We recommend a 750 W unit (80 Plus Gold or better) so transient spikes from the graphics card stay inside the PSU's comfort zone. Try other pairs in the PSU calculator.

Best CPU for the RTX 3090 Best GPU for the Core i5-10400F RTX 3090 PSU requirements

Compare nearby pairs

Same CPU, other GPUs

Same GPU, other CPUs

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