CPU_VS_GPU / 2026-09-11
Intel Core Ultra 5 245KFvsNVIDIA RTX 5090
Complete bottleneck analysis at 1080p, 1440p, Ultrawide (UWQHD/SUWQHD), and 4K with estimated FPS for popular games.
35%
RESOLUTION LIMIT (GPU OVERKILL)
Your GPU (RTX 5090) has more capacity than 2560x1440 can use, even with a CPU as fast as the Core Ultra 5 245KF: around 35% of it sits idle. A higher resolution or heavier settings would put that capacity to work; that buys image quality rather than frames, so the frame rate will come down, not up.
Load estimated by the model, not measured on your PC.
- PROCESSORIntel Core Ultra 5 245KF
- GRAPHICSNVIDIA RTX 5090
- MEMORY16GB DDR4/DDR5
- RESOLUTION2560x1440
Average across the demanding titles at 2560x1440.
Average across the competitive titles, where the processor leads.
What the build draws (850 W) plus headroom.
DEEP-DIVE ANALYSIS
GENERATED BY THE ENGINEPairing the Intel Core Ultra 5 245KF (83/100 on our gaming index) with the NVIDIA RTX 5090 (96/100) raises one practical question: do they pull together, or does one hold the other back? We ran this exact combination across all supported resolutions to answer it with numbers rather than guesswork.
Quick take: 5K is the resolution to target
At 1080p the RTX 5090 has power to spare and sits partly idle, whereas at 4K the two stay well balanced. We put the target at 5K: the highest of the usual 16:9 sizes where AAA titles still return 68 FPS, which is above 60. The table below breaks out all twelve resolutions on their own, ultrawide formats included.
Think of resolution as a dial that splits the weight between CPU and GPU. Drop to 1080p and you wring out the RTX 5090 while leaning harder on the Core Ultra 5 245KF; push to 4K and the opposite happens. Synergy here swings between 100% and 52% depending on where you sit.
Down to real numbers: In esports titles like Valorant this pair flies — around 773 FPS at 1080p, plenty for a high-refresh monitor. At the other end, a demanding AAA like Elden Ring drops to ~60 FPS at 4K, which is where the RTX 5090's ceiling really shows. Overall, expect about 132 FPS average in AAA games at 1080p and around 91 FPS at 4K.
[CPU] Core Ultra 5 245KF
The Core Ultra 5 245KF scores 83/100 on this model's gaming scale, with 14 cores and 14 threads. In this pairing its job is to serve frames fast enough to never leave the graphics card waiting.
[GPU] RTX 5090
The RTX 5090 (96/100 on the model's gaming scale) supplies the raster muscle of the build. Its 32 GB of GDDR7 set how far it can go on resolution and texture quality before video memory runs short.
On the chemistry of the pair: Both parts come from nearby generations, which usually means a natural pairing with no platform surprises. You're combining an Intel platform with an NVIDIA GPU — a perfectly valid mix that imposes no penalty.
DO YOU NEED TO CHANGE ANYTHING?
At 1440p the RTX 5090 has capacity to spare, and no part swap would raise the frame rate noticeably. A higher resolution or heavier settings put that capacity to work — that buys image quality, not frames, so expect the frame rate to come down rather than up. If 1440p is enough for you, nothing needs changing.
PRICE OF EACH PART
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SPECIFICATIONS
CATALOGUE DATA[CPU] Intel Core Ultra 5 245KF
- Cores14C / 14T
- Clock4.2 – 5.2 GHz
- TDP125 W
- SocketLGA1851
- Single-thread4,713
- Multi-thread43,109
- L3 cache24 MB
[GPU] NVIDIA RTX 5090
- VRAM32 GB GDDR7
- Memory bus512-bit
- TDP575 W
- G3D Mark57,120
- Memory bandwidth1792 GB/s
BOTTLENECK BY RESOLUTION
SYNERGY · AVERAGE FPSYour GPU (RTX 5090) has far more capacity than 1920x1080 can use: around 48% of it sits idle. Stepping up to 1440p or 4K would put that capacity to work at the cost of some frames: you gain sharpness, not speed.
Your GPU (RTX 5090) has more capacity than 2560x1440 can use, even with a CPU as fast as the Core Ultra 5 245KF: around 35% of it sits idle. A higher resolution or heavier settings would put that capacity to work; that buys image quality rather than frames, so the frame rate will come down, not up.
Your CPU (Core Ultra 5 245KF) introduces a slight limitation at 3440x1440 (Ultrawide 21:9). Real-world impact is small and both components work well together.
Your CPU (Core Ultra 5 245KF) and GPU (RTX 5090) are an exceptionally balanced match for gaming at 5120x1440 (Super Ultrawide 32:9). No realistic component swap would meaningfully improve this build.
Your CPU (Core Ultra 5 245KF) and GPU (RTX 5090) are an exceptionally balanced match for gaming at 4K. No realistic component swap would meaningfully improve this build.
ESTIMATED FPS BY GAME
1920x1080SYSTEM DIAGNOSTICS
POWER · VRAM & PCIe · RAMPOWER ESTIMATION
The Core Ultra 5 245KF (125W) and RTX 5090 (575W) add up to roughly 700W under load. Adding 150W for the rest of the system gives 850W, and with a 30% transient margin, 1150W is the safe figure.
VIDEO MEMORY AND PCIe
The RTX 5090's memory bus (512-bit) and bandwidth (1792 GB/s) describe its own video memory, meaning how fast the card reads its 32 GB of GDDR7, not the PCIe link to the processor. The PCIe link depends on the card, the processor and the motherboard slot together; our catalogue does not record PCIe generation or lane count, so the model does not estimate it. It matters most for cards with an eight-lane interface in older PCIe 3.0 boards: check the card's and the board's specifications.
SYSTEM MEMORY
This page assumes 16 GB in dual channel. At 5K, the resolution recommended above, that meets the model's capacity target of 16 GB (enough for three in four of the games it covers), so more capacity would add little or nothing there. The target stays at 16 GB even at 4K, so a larger kit is for heavy multitasking or mods, not for these games. Memory speed and a second channel act on the processor's ceiling instead: they matter in the games the CPU limits, by an amount that depends on the game, and the calculator lets you enter your own kit.
HOW THIS PAGE IS CALCULATED
ENGINE v2026.08 · 2026-09-11CALCULATED, NOT WRITTEN
Every figure and every sentence comes from the same deterministic engine, driven by the catalogue specifications. That is what makes it reproducible: with the same engine version (2026.08) and the same catalogue, the same pairing always gives the same result. When either changes, the version and date above change with it, and the changelog says why.
WHERE THE DATA COMES FROM
Specifications come from the official AMD, Intel and NVIDIA datasheets together with PassMark and TechPowerUp. The gaming indices are calibrated against frame rates published by review outlets (TechPowerUp, TechSpot / Hardware Unboxed, Tom's Hardware, Gamers Nexus, Digital Foundry) rather than synthetic scores. That data is compiled, not measured here: this site runs no test bench of its own.
STATED LIMITS
Figures estimate native raster performance at high/ultra quality, with no ray tracing, upscaling or frame generation. We do not yet publish an externally validated error margin — the accuracy page states exactly where that stands.
* Affiliate disclosure: the Amazon links exist to show pricing. As an Amazon Associate we earn from qualifying purchases at no extra cost to you. Recommendation order is decided by the engine and does not depend on commission.
TRY WITH YOUR OWN HARDWARE
Customize RAM, resolution, and discover upgrade recommendations.
FREQUENTLY ASKED QUESTIONS
5Does the Intel Core Ultra 5 245KF bottleneck the NVIDIA RTX 5090?
At 1080p the RTX 5090 has power to spare and sits partly idle, whereas at 4K the two stay well balanced. Overall, there is some mismatch depending on resolution, with 82% average efficiency across the 12 resolutions our model tests. The resolution we would target with this pair is 5K, where AAA games average 68 FPS.
How many FPS do the Core Ultra 5 245KF and RTX 5090 get at 1080p?
At 1080p this combination averages about 132 FPS in AAA games and around 456 FPS in esports titles. In Valorant we estimate up to 773 FPS.
Is this pairing good for 4K gaming?
Yes. At 4K this pairing averages about 91 FPS in AAA titles, at or above the 60 FPS we treat as smooth.
What power supply do I need for the Core Ultra 5 245KF and RTX 5090?
With an estimated combined draw of 700W across CPU and GPU, we recommend at least an 1150W 80+ Gold supply (ideally ATX 3.0) to run with headroom.
Is the RTX 5090's 32 GB of VRAM enough?
In the model, 32 GB covers all 11 games it tracks even at 4K with high textures, so video memory is not the constraint for this pairing.