CPU_VS_GPU / 2026-09-11
Intel Core i5-9400FvsNVIDIA RTX 4070 SUPER
Complete bottleneck analysis at 1080p, 1440p, Ultrawide (UWQHD/SUWQHD), and 4K with estimated FPS for popular games.
31%
ESTIMATED CPU BOTTLENECK
Your CPU (Core i5-9400F) cannot feed the RTX 4070 SUPER fast enough at 2560x1440. The GPU sits waiting for frames, causing stutter and noticeable drops. A CPU upgrade is the highest-impact change you can make.
Load estimated by the model, not measured on your PC.
- PROCESSORIntel Core i5-9400F
- GRAPHICSNVIDIA RTX 4070 SUPER
- MEMORY16GB DDR4/DDR5
- RESOLUTION2560x1440
Average across the demanding titles at 2560x1440.
Average across the competitive titles, where the processor leads.
What the build draws (435 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 4070 SUPER. The processor scores 46/100 and the graphics card 49/100 in our model — the interesting part is how they split the workload at each resolution.
Quick take: 1440p is the resolution to target
At 1080p the Core i5-9400F becomes the limiting part (~54% CPU bottleneck), whereas at 4K the two stay well balanced. Of the common 16:9 sizes, the highest this pair holds above 60 FPS in AAA titles is 1440p, where it averages 63 FPS — that is the resolution worth buying a monitor for. Across every resolution tested, ultrawides included, the system runs at 71% average efficiency.
Resolution reshuffles the priorities. At 1080p the Core i5-9400F's single-thread speed calls the shots; at 4K it's the raw muscle of the RTX 4070 SUPER that matters. That shift shows up in the numbers: 46% efficiency at 1080p versus 95% at 4K.
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 ~26 FPS at 4K, which is where the RTX 4070 SUPER's ceiling really shows. Overall, expect about 66 FPS average in AAA games at 1080p and around 45 FPS at 4K.
[CPU] Core i5-9400F
On the CPU side: the Core i5-9400F rates 46/100 for gaming in this model and brings 6 cores and 6 threads. At lower resolutions it's the one setting the pace for the whole system.
[GPU] RTX 4070 SUPER
The RTX 4070 SUPER (49/100 on the model's gaming scale) supplies the raster muscle of the build. Its 12 GB of GDDR6X set how far it can go on resolution and texture quality before video memory runs short.
Beyond the FPS: The graphics card is about 5 years newer than the processor, so watch that the Core i5-9400F doesn't fall short in the most CPU-dependent games. You're combining an Intel platform with an NVIDIA GPU — a perfectly valid mix that imposes no penalty.
WHAT TO CHANGE, AND WHAT IT COSTS
At 1440p the Core i5-9400F sets the frame rate and leaves part of the RTX 4070 SUPER idle. The cheapest processor in our catalogue that keeps the card fully fed and clears our bar (at least 10% more frames) is the AMD Ryzen 5 5600: about 48% more in this model, with this card and 16 GB. It uses a different socket (AM4 instead of LGA1151), so the cost includes a motherboard.
The gain is the model's estimate at 2560x1440 with 16 GB, not a measurement of your PC, and prices change: check them at the retailer before deciding.
PRICE OF THIS PAGE'S PAIRING
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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 4070 SUPER
- VRAM12 GB GDDR6X
- Memory bus192-bit
- TDP220 W
- G3D Mark31,814
- Memory bandwidth504 GB/s
BOTTLENECK BY RESOLUTION
SYNERGY · AVERAGE FPSYour CPU (Core i5-9400F) cannot feed the RTX 4070 SUPER 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) cannot feed the RTX 4070 SUPER fast enough at 2560x1440. 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) partially limits the RTX 4070 SUPER at 3440x1440 (Ultrawide 21:9). In CPU-heavy scenes you will lose frames. Consider a CPU upgrade or a higher target resolution.
Your CPU (Core i5-9400F) and GPU (RTX 4070 SUPER) 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 i5-9400F) and GPU (RTX 4070 SUPER) 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 i5-9400F (65W) and RTX 4070 SUPER (220W) add up to roughly 285W under load. Adding 150W for the rest of the system gives 435W, and with a 30% transient margin, 600W is the safe figure.
VIDEO MEMORY AND PCIe
The RTX 4070 SUPER's memory bus (192-bit) and bandwidth (504 GB/s) describe its own video memory, meaning how fast the card reads its 12 GB of GDDR6X, 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 1440p, 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 4070 SUPER?
At 1080p the Core i5-9400F becomes the limiting part (~54% CPU bottleneck), whereas at 4K the two stay well balanced. Overall, there is some mismatch depending on resolution, with 71% average efficiency across the 12 resolutions our model tests. The resolution we would target with this pair is 1440p, where AAA games average 63 FPS.
How many FPS do the Core i5-9400F and RTX 4070 SUPER get at 1080p?
At 1080p this combination averages about 66 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 45 FPS on average in AAA titles at 4K. 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 4070 SUPER?
With an estimated combined draw of 285W across CPU and GPU, we recommend at least a 600W 80+ Gold supply (ideally ATX 3.0) to run with headroom.
Is the RTX 4070 SUPER's 12 GB of VRAM enough?
12 GB covers all 11 tracked games at 1440p in the model; at 4K, 3 of them would need more, which costs frames or texture quality in those titles.