Will the Core i9-12900K bottleneck the GTX 1080 Ti?

No. At 1440p the GTX 1080 Ti is the limiting part, which is the normal state for a gaming PC. The Core i9-12900K has headroom to spare. This is a model estimate from performance indexes, not a measured FPS loss.

What power supply do I need for a Core i9-12900K and GTX 1080 Ti?

Sustained gaming load is about 547 W using the GTX 1080 Ti's measured draw. A 850 W unit is the safe choice.

Is this pair better at 1080p or 4K?

1080p: GPU-limited 24% (GPU-bound (normal)). 1440p: GPU-limited 31% (GPU-bound (normal)). 4K: GPU-limited 47% (CPU overkill).

Core i9-12900K + GTX 1080 Ti: bottleneck check

31%

GPU-limited at 1440p. GPU-bound (normal).

CPU GPU

The GTX 1080 Ti is the part working hardest at 1440p, which is what you want. The Core i9-12900K keeps about 31% in reserve.

By resolution

Resolution	Limiting part	Severity	Verdict
1080p	GPU	24%	GPU-bound (normal)
1440p	GPU	31%	GPU-bound (normal)
4K	GPU	47%	CPU overkill

The GTX 1080 Ti is the limit at every resolution and by a wide margin at 4K (47%). The Core i9-12900K is overkill for this card: a faster GPU would give you far more frames than any CPU change.

Specifications

Intel Core i9-12900K
Cores / threads	16 / 24
Max boost	5.2 GHz
Socket	LGA1700
Maximum turbo power (MTP)	241 W Intel's published maximum sustained turbo power, above its base power; the PSU estimate uses it, so it errs high · Intel ARK
Released	2021
Gaming index	78 / 100
Multi-core index	80 / 100

NVIDIA GeForce GTX 1080 Ti
VRAM	11 GB
Board power	250 W
Released	2017
1080p index	28.7 / 100
1440p index	23 / 100
4K index	18.4 / 100

Power supply

The GTX 1080 Ti measured 231 W average while gaming (267 W peak, TechPowerUp). With the Core i9-12900K at its maximum turbo power of 241 W and about 75 W for the rest of the system, the sustained load is about 547 W. A 850 W unit is the safe choice. Details on the GTX 1080 Ti PSU page or try other pairs in the PSU calculator.

Upgrade paths

CPUs that remove the bottleneck

LGA1700

Cards that use the Core i9-12900K fully

Best CPU for the GTX 1080 Ti Best GPU for the Core i9-12900K GTX 1080 Ti PSU requirements

Same CPU, other cards

All

Same card, other CPUs

All

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