Can I increase the clock speed of my i7 4790k to around 4.8 GHz?
Can I increase the clock speed of my i7 4790k to around 4.8 GHz?
CPU: Intel Core i5 4790K 4.0 GHz (Haswell) *4
Motherboard: ASUS Z87M-Plus mATX
Memory: A-Data 8GB (2x4GB) CL9 1600MHz XPG + Crucial 8GB (2*4096MB) CL8 1600MHz Ballistix Elite
Storage: 1TB Seagate Barracuda 7200rpm 64MB and Intel 330 Series 2.5" 120GB SSD Sata/600 MLC 25NM
GPU: 1 x Powercolor Radeon RX 590 8GB Red Dragon
Power Supply: Fractal Design Integra R2 650W 80+ Bronze
Case: Cooler Master Silencio 352
Operating System: Microsoft Windows 10 Pro
Display: ASUS VP247 @ 82 Hz
Hi,
I managed to successfully overclock my i7 4790K to 4.7GhZ with Vcore at 1.31 and Vccin at 1.85.
Many users have reported further improvements, hoping for a minimum of 4.8GhZ from this CPU.
I attempted configurations with Vcore up to 1,355GHz and Vccin at 1.9, but the system became unstable during stress tests.
Some sources suggest that exceeding 1.35V for a 4790K is risky, so I haven’t pushed the voltage further.
Dercie
,
Each processor stands apart from the others; their differences lie in voltage limits, heat management, and overclocking capabilities—a phenomenon often called the "silicon lottery."
Overclocking is constrained by two main aspects: voltage and temperature.
Because overclocked units can exceed 50% above their rated TDP, effective cooling becomes essential.
While the Throttle temperature for the 4790K reaches 100°C, most knowledgeable reviewers, system designers, and seasoned overclockers agree it's wise to maintain a safe thermal buffer below this threshold for stability, performance, and durability. This applies regardless of the surrounding environment.
This updated version offers a smoother gaming session, maintaining around 10 FPS even at higher settings before performance issues arise.
Each processor is unique.
Your version might only work reliably up to 4.7 max.
Ok, a couple things. You posted your specs but when talking about wanting to overclock and push a 4790 past 1.35v and to try for 5Ghz you left out arguably the most important thing: what is your cooling solution? Are you running the bog standard Hyper 212, a 240 or 360 AIO, are you fully open loop cooled? If you are on air, even with something great like the Noctua D14, I would suggest not going past 1.35 and deffintely not to 1.4, and maybe just forgo trying to hit 5Ghz. Even on an AIO I would doubt your temps would be where you'd want them. When the 4790k dropped there was a decent amount of buzz about how this was the first 5Ghz i7 and whatnot. Personally I think that was a bunch of bull and random people trying to show off their E-peen claiming they could hit 5Ghz at absolutely unrealistic voltages. Its just my personal opinion "real" 5Ghz chips didn't come until later. The amount of 4790s even able to hit 5Ghz at
any
voltage is very low, especially if being 100% stable means anything to you and you don't want random and frequent BSoDs and always being afraid of losing game progress or doing something non game related and losing your work.
I spent the first few years tinkering with clock speeds, voltages, bus speeds, RAM timings, all the fun stuff trying to sqeak out that last 1% of performance until I eventually got tired of doing it. I will say, as good as my silicone is/was being a decent lottery winner, I was never able to hit 5Ghz-and believe me I tried. Sure, I
could
get my computer to post and boot into windows at 5Ghz, but it was so unstable that no one in their right mind would ever want to keep it there. At my highest, I was able to maintain a 4.85+ OC at 1.29 and a 46x cache and be 90% stable, however that wasn't solely on multiplier alone but with a bump in bus speed which is probably where that random 10% instability came from. As a side note, I could never keep my system stable if I pushed my cache beyond 46 at any voltage for either the Vcore or the cache; even if I went to 47 cache and underclocked the CPU, it was unstable. The clock I've settled with for the past many years has been 4.71 @ 1.26 and a 46x cache. That is a decent bump over the stock 4.4 and I am 100% stable and my temps are icy cool. People claiming they were hitting 4.8 at 1.25 and 5Ghz at 1.3 without ever showing proof of those speeds and moreso proof of stability at those speeds and voltages I never believed.
TL;DR
You're going to want to be on more than air cooling when talking about those vcore numbers.
A good deal of 4790s won't hit 5Ghz no matter how much voltage you pump into them.
I'm no expert or engineer or some minor celeb on Youtube, but I would not advise running a 4790 24/7 at 1.35-1.4 volts. I completely understand the feeling that our chips are getting a bit long in the tooth and wanting to sqeeze every bit of performamce out of them now more than ever, to keep up with modern releases and tide us over until computer prices become somewhat normal again. But especially during these times with everything the way it is, I wouldn't suggest going to the absolute limit. Even if theoretically you could maintain 5Ghz at 1.4 volts, you're probably going to kill that thing orders of magnitude faster than you would running it at 4.6 or 4.7 and under 1.3 volts and just deal with not having the extra 5 FPS or whatever.
The processors differ significantly; no two are the same in terms of voltage limits, heat management, and overclocking capability—a phenomenon often called the "silicon lottery."
Overclocking is constrained mainly by voltage and temperature.
Because overclocked units can exceed 50% above their rated TDP, effective cooling solutions such as high-performance air or liquid systems become essential.
Even though the Throttle temperature for the 4790K reaches 100°C, experts—ranging from seasoned reviewers to system designers and expert overclockers—consistently advise maintaining a comfortable thermal buffer below this threshold for optimal stability, performance, and durability. This advice remains valid regardless of environmental factors, hardware setups, or workload demands.
Temperatures exceeding 85°C are discouraged.
Therefore, the standard operating temperature window is clearly defined:
Core temps under 80°C are preferred.
These temperatures fluctuate with room conditions; the accepted "normal" range aligns with 22°C or 72°F.
Each microarchitecture, measured in nanometers (nm), has a specific "Maximum Recommended Vcore."
For instance, 22nm processors from the third and fourth generations cannot handle higher core voltages than their predecessors.
Since excessive voltage and heat over time harm electronic components, manually adjusting Vcore in BIOS can lead to accelerated electromigration—damaging delicate circuits and reducing stability.
Even if your initial overclock works, gradual degradation becomes evident through more frequent crashes or instability.
Reducing overclock and Vcore can temporarily restore performance and slow further wear.
However, extreme voltage spikes may cause immediate damage, though a well-managed overclock can remain stable for years.
Each microarchitecture also features a "Degradation Curve," showing how voltage thresholds shift with temperature.
CPUs are generally more vulnerable to electromigration as they shrink, but the 14nm generation stands out due to FinFET technology improvements.
The degradation curves differ between generations, especially for 22nm (third and fourth) versus higher-numbered ones.
Higher voltages accelerate Vt shifts, which can impair transistor function over time.
Excessive heat and prolonged stress eventually degrade performance, so monitoring and limiting voltage is crucial.
Staying within recommended limits ensures long-term reliability and consistent results.
4.8 versus 4.7 represents a 2% variation. Even with perfect scaling, reaching a 2% improvement would require 500 FPS to achieve a 10 FPS gain. It seems another factor likely influenced the 10 FPS difference.
The Vccin value of 1.9 doesn’t ensure stability or performance; it was increased from 1.8. My 3770k reached stable operation at 5.0GHz by lowering the Vccin to 1.7. To get the best performance from the CPU, you’ll need significantly more effort than just adjusting Vcore and Vccin. Ring voltages must be kept within limits (avoid extreme or maximum settings), power delivery should be increased, phase configurations require careful tuning rather than simple energy-saving tricks, turbo timers, c-states, and other power-saving features must remain disabled. System Agent tweaks and similar adjustments are also essential.
Very few 4th generation CPUs reach 4.8GHz or higher; most are limited by voltage constraints well before achieving such speeds. Generally, you should stay within a range of around 1.2V to 1.25V, depending on your needs. Since power consumption is directly related to resistance in the CPU and the constant current draw, the biggest improvements come from optimizing current, impedance, or resistance rather than relying solely on voltage changes. These adjustments depend heavily on your motherboard and VRM capabilities. If your PSU can’t supply clean power under higher loads, you won’t achieve stable high overclocking.
Fps depends on the CPU’s clock speed, cycles per instruction, or IPC—higher clocks mean more instructions processed per second, leading to better FPS. Increasing the clock from 4.7 to 4.8GHz only gives about a 5% improvement, translating to roughly a 2% boost in FPS overall. A noticeable jump to 10fps in Warzone is only significant if you’re far below 60fps. Going beyond 200fps becomes negligible; the difference is often just a small margin and may not be perceptible.