CPU_VS_GPU / 2026-09-11
Intel Core i5-9400FvsNVIDIA RTX 2080 Ti
Complete bottleneck analysis at 1080p, 1440p, Ultrawide (UWQHD/SUWQHD), and 4K with estimated FPS for popular games.
7%
PERFECTLY BALANCED BUILD
Your CPU (Core i5-9400F) and GPU (RTX 2080 Ti) are an exceptionally balanced match for gaming at 2560x1440. No realistic component swap would meaningfully improve this build.
Load estimated by the model, not measured on your PC.
- PROCESSORIntel Core i5-9400F
- GRAPHICSNVIDIA RTX 2080 Ti
- MEMORY16GB DDR4/DDR5
- RESOLUTION2560x1440
Average across the demanding titles at 2560x1440.
Average across the competitive titles, where the processor leads.
What the build draws (465 W) plus headroom.
DEEP-DIVE ANALYSIS
GENERATED BY THE ENGINEThis page breaks down, number by number, what happens when you run an Intel Core i5-9400F alongside an NVIDIA RTX 2080 Ti. The processor scores 46/100 and the graphics card 31/100 in our model — the interesting part is how they split the workload at each resolution.
Straight answer: aim for 1080p
At 1080p the Core i5-9400F becomes the limiting part (~34% CPU bottleneck), whereas at 4K the RTX 2080 Ti is the limiting part (~32% GPU bottleneck). We put the target at 1080p: the highest of the usual 16:9 sizes where AAA titles still return 61 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 2080 Ti while leaning harder on the Core i5-9400F; push to 4K and the opposite happens. Synergy here swings between 68% and 66% depending on where you sit.
In esports titles like Valorant this pair flies — around 275 FPS at 1080p, plenty for a high-refresh monitor. At the other end, a demanding AAA like Alan Wake 2 drops to ~15 FPS at 4K, which is where the RTX 2080 Ti's ceiling really shows. Overall, expect about 61 FPS average in AAA games at 1080p and around 30 FPS at 4K.
[CPU] Core i5-9400F
The Core i5-9400F scores 46/100 on this model's gaming scale, with 6 cores and 6 threads. In this pairing its job is to serve frames fast enough to never leave the graphics card waiting.
[GPU] RTX 2080 Ti
On the graphics side, the RTX 2080 Ti rates 31/100 for gaming in this model. Its 11 GB of GDDR6 set how far it can go on resolution and texture quality before video memory runs short. The higher the resolution, the more of the frame rate depends on it.
A detail that's easy to overlook: 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 neither part appreciably holds the other back, so there is nothing you need to change. The Core i5-9400F and the RTX 2080 Ti stand as they are; a 650W supply gives the build headroom.
PRICE OF EACH PART
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SPECIFICATIONS
CATALOGUE DATA[CPU] Intel Core i5-9400F
- Cores6C / 6T
- Clock2.9 – 4.1 GHz
- TDP65 W
- SocketLGA1151
- Single-thread2,421
- Multi-thread9,457
- L3 cache9 MB
[GPU] NVIDIA RTX 2080 Ti
- VRAM11 GB GDDR6
- Memory bus352-bit
- TDP250 W
- G3D Mark21,884
- Memory bandwidth616 GB/s
BOTTLENECK BY RESOLUTION
SYNERGY · AVERAGE FPSYour CPU (Core i5-9400F) cannot feed the RTX 2080 Ti fast enough at 1920x1080. The GPU sits waiting for frames, causing stutter and noticeable drops. A CPU upgrade is the highest-impact change you can make.
Your CPU (Core i5-9400F) and GPU (RTX 2080 Ti) are an exceptionally balanced match for gaming at 2560x1440. No realistic component swap would meaningfully improve this build.
Your CPU (Core i5-9400F) and GPU (RTX 2080 Ti) are an exceptionally balanced match for gaming at 3440x1440 (Ultrawide 21:9). No realistic component swap would meaningfully improve this build.
Your GPU (RTX 2080 Ti) is the limiting factor at 5120x1440 (Super Ultrawide 32:9). In graphically demanding titles you will see lower frame rates; a faster GPU would deliver a clear improvement.
Your GPU (RTX 2080 Ti) severely limits the system at 4K, leaving the Core i5-9400F heavily underused. A faster GPU would improve performance dramatically.
ESTIMATED FPS BY GAME
1920x1080SYSTEM DIAGNOSTICS
POWER · VRAM & PCIe · RAMPOWER ESTIMATION
The Core i5-9400F (65W) and RTX 2080 Ti (250W) add up to roughly 315W under load. Adding 150W for the rest of the system gives 465W, and with a 30% transient margin, 650W is the safe figure.
VIDEO MEMORY AND PCIe
The RTX 2080 Ti's memory bus (352-bit) and bandwidth (616 GB/s) describe its own video memory, meaning how fast the card reads its 11 GB of GDDR6, 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 1080p, 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 i5-9400F bottleneck the NVIDIA RTX 2080 Ti?
At 1080p the Core i5-9400F becomes the limiting part (~34% CPU bottleneck), whereas at 4K the RTX 2080 Ti is the limiting part (~32% GPU bottleneck). Overall, the GPU is the limit at high resolution, with 69% average efficiency across the 12 resolutions our model tests. The resolution we would target with this pair is 1080p, where AAA games average 61 FPS.
How many FPS do the Core i5-9400F and RTX 2080 Ti get at 1080p?
At 1080p this combination averages about 61 FPS in AAA games and around 172 FPS in esports titles. In Valorant we estimate up to 275 FPS.
Is this pairing good for 4K gaming?
Playable rather than smooth: about 30 FPS on average in AAA titles at 4K, with the RTX 2080 Ti setting the limit. Upscaling (DLSS, FSR or XeSS) or lower settings are the usual way to reach 60 FPS.
What power supply do I need for the Core i5-9400F and RTX 2080 Ti?
With an estimated combined draw of 315W across CPU and GPU, we recommend at least a 650W 80+ Gold supply (ideally ATX 3.0) to run with headroom.
Is the RTX 2080 Ti's 11 GB of VRAM enough?
11 GB covers all 11 tracked games at 1440p in the model; at 4K, 4 of them would need more, which costs frames or texture quality in those titles.