Overclocking the i7 4790k
Overclocking the i7 4790k
After examining reviews, I successfully achieved 4.8ghz with a manual 1.375vcore (system boosts it to 1.392) and the CPU idles smoothly on Windows. Under heavy load, it reached 100c and throttled without crashing. Any setting below 1.375vcore caused an instant crash. I experimented with 4.9ghz and 5ghz, but all experienced instability, with 5ghz leaving it at a high voltage and 4.6ghz settling at 4.5ghz. Idle temperatures stayed around 28c using the Sunbeam Core Contact Freezer as a cooling solution. When testing Far Cry 3, I faced crashes after adjusting the vcore, so I settled on 4.5ghz for stability. The decision now leans toward keeping it at 4.5ghz to ensure longevity, possibly revisiting 4.8 if the Hyper212 proves more capable. Anyone know if someone has achieved stable 4.8ghz on air?
Once you hit the stable overclock possible at a maximum Vcore of 1.300, it's time to celebrate and grab a beer! I tested several i7 4770K processors before finding one that ran smoothly at 4.7GHz with a 1.280 Vcore. It’s truly a matter of chance! You should also check out the full Sticky article: Intel Temperature Guide - "... Section 8 - Overclocking and Vcore Processors boosted to high speeds can hit up to 150% of their Thermal Design Power (TDP) with manual Core voltage settings. That means strong cooling solutions are essential. Each chip behaves differently in terms of overclocking ability, voltage limits, and heat management. No matter what, too much Vcore and heat will speed up 'Electromigration' – a process that damages internal traces and junctions. This can cause blue-screen errors that grow more common over time. CPUs are getting more vulnerable to Electromigration with each generation, so the 22 Nanometer design is less forgiving when it comes to over-voltage. Still, Vcore values should stay within these guidelines: -> Core 2 1st Gen 65nm... 1.50 Vcore 2nd Gen 45nm... 1.40 Vcore -> Core i 1st Gen 45nm... 1.40 Vcore 2nd Gen 32nm... 1.35 Vcore -> Core 3 1st Gen 22nm... 1.30 Vcore 4th Gen 22nm... 1.30 Vcore When adjusting your processor near its top overclock, remember that for every 100 MHz increase, you’ll typically need about 40 to 50 millivolts more (0.040 to 0.050)...."
Nice info CT. I've found a stable setting at 4.5Ghz with a vcore of 1.232. I tried 4.7 at 1.292vcore and 1.280 but had no luck. 4.6Ghz seems tricky—might be better to skip it for longer stability. This chip is still really good! Thanks for the advice!
the die-shrink isn’t related to the MAX voltage. additionally, they also employ 32nm technology and utilize 1.5volt stock. reducing a mosfet or transistor size doesn’t necessarily lower the voltage consumption. a smaller device will draw less current compared to a larger one, yet it can still deliver the same output. particularly with modern intel processors that use 3dgates, this is common. the gate in a mosfet functions similarly to a capacitor. each clock cycle causes it to charge or discharge this component until the voltage at the junction reaches its threshold—this isn’t the maximum voltage. therefore, increasing frequency leads to more current flow. current multiplied by voltage equals power consumption. the junction voltage for typical transistors is around 0.6 volts; anything higher doesn’t produce noticeable effects. however, raising the switching voltage boosts current through capacitors so they reach the junction faster. a diagram from techitoutuk illustrates this process, showing how a capacitor charges under applied voltage. if you apply 0.6 volts, it takes about 15 seconds to switch the transistor; at 1.2 volts it’s 7.5 seconds, and at 1.8 volts roughly 4 seconds. thus, increasing voltage is necessary to achieve the desired switching speed. but what truly damages transistors or mosfets is sudden current spikes caused by excessive voltage application. power usage rises significantly: frequency nearly doubles power consumption. for example, a 3ghz processor using 100 watts would require around 133 watts at 4ghz. when voltage increases, both current and voltage rise simultaneously to charge capacitors more quickly. if 1.3 volts delivers 100 watts, then 1.4 volts would need about 115.9 watts, and 1.5 volts around 133 watts. this shows that higher voltages are essential for maintaining performance without overheating components.
Idle temps are 28c with sunbeam core contact freezer as a heat sink. I have a hyper212 evo arriving soon, but I might just wait and see. My main thought is that a 4.8ghz could work with a top-tier air cooler, but I prefer a steady 4.5ghz to extend its lifespan. Perhaps I’ll revisit 4.8 if the hyper212 proves more capable than this SCCF. You won’t achieve extreme cooling performance between the Sunbeam Core Contact Freezer and the CMH212EVO, and it’s possible you’ve spent too much on the EVO. Both units are quite outdated despite their popularity; as long as they’re affordable, the cooling power reflects the price. We all care a bit about CPU longevity unless you’re the kind of person in the Geico ad who cares more about money than performance. It’s crucial to manage CPU load temperatures relative to applied voltage, especially if you opt for air cooling. The most advanced passive coolers can handle moderate heat without needing an active fan. These high-end heat pipe air coolers are expensive because they’re passive and work best with mounted fans. Take the time to read the link below for more details on air and water cooling options:
With the evo, my temperatures fell by about 10 degrees compared to the sunbeam. Now I'm getting 22-25 degrees idle and around 40s under load, instead of the 35s in the 50s before. My sunbeam was also quite old. The CPU is running smoothly at 4.6ghz.
The best performance I got on air was 4.5GHZ @ 1.12v. Even with the low voltage, temperatures stayed high, in the upper 70s to low 80s.
I just transferred my CPU/mobo into a new case with a 360mm water cooler, which brought it up to 5.0GHZ stable at 1.329 volts. I could also run 4.9GHZ at 1.26v.
mikiwroc :
I think, i'm really lucky, because i'm stable with my 4790k at 4,8ghz 1.270 vcore
Yes mine is like this as well. Glad I got a good sample. 4.8 is my limit before I have to tweak the vcore though
🙁
. I feel like it can hit 5 but there is no need for me to do so right now.
If you think about it though what is the real difference of 100MHz between 4.4 and 4.5. Seems like a waste of time and electric to do that. If you are only gaming then there is no point. No game even comes close to making the 4790k sweat @ stock. Even if doing CPU intensive task like video rendering, thats only a few seconds saved at best.