Enhanced, secured i7-4790 model
Enhanced, secured i7-4790 model
Today I enhanced the performance of a 4790 i7 CPU that’s over 3 years old. The motherboard used was Gigabyte Z97X UD3H, and the memory consisted of four 8GB DDR3 DIMMs at 1600MHz. The PSU was Corsair RM 850. Before upgrades all cores ran at 3.8 GHz, single core at 4.0 GHz. After adjustments the speeds improved to 3.91 GHz for all cores and 4.11 GHz for single core. The CPU score is 7684, with an average idle temp of 48°C and a max of 94°C.
Experimented by switching the FSB speed from 100 MHz to 103 MHz, adjusting RAM voltage from auto to 1.5V (using three 1.35V and one 1.6V), and changing RAM speeds from 1600 MHz to 1648 MHz. I tried increasing RAM voltage to 1.6V but it didn’t work—likely because the default voltage is 1.35V. Any suggestions for further improvements?
Avoid exceeding the voltage limits of your RAM; doing so can damage it. This setup uses DDR3.
1.5 works fine. However, 1.6 tends to be too high for DDR3, which might cause issues with the 1.35V supply.
The core problem isn’t the clock adjustment itself, but rather the voltage and temperature limits. A 1.6V supply for DDR3 is risky, and pushing temperatures too high will cause damage. RAM speed isn’t a major concern on Haswell, especially with modest increases. Cooling becomes critical—overclocking in a stock cooler or even at 94°C is dangerous. Dock cooling would only extend the time under stress. For your RAM, stick to the XMP settings or adjust timings instead of boosting voltage. If you lack XMP profiles, it may be best not to increase voltage further.
Yes, setting the GPU frequency to 1400 MHz is possible and often recommended for better performance.