wsarahan :
Hi guys how are you?
I have a doubt here, i have an i7 4770k @ 4.5 with 1.3vcore
I was looking at bios trying to increase something and saw that my uncore ratio was set to auto, and the bios suggest that the uncore be the same or higher than core ratio
is it true? Should i put auto off and set the uncore to 45 as well? Will i have some real gain? Can happen any issue like instability?
Edit: Another question, I`m using 1.31 vcore to 4.6, do you think i can reach a stable Oc with less? I know that the basically to more than 4.5 we will need something about 1.3 to more right? Or am i wrong?
EXPLANATION
UNCORE (= not core, not CPU) is easy to set. This post is valid for Skylake 6600k / 6700k on any motherboard (Gigabyte, Asus, etc.). Among other things, the Uncore Ratio relates to the frequency of the cache used by the CPU. And you have to manually set the Uncore Ratio in the BIOS of the motherboard because it remains stuck at the stock ratio of 35 (3.5 GHz) even after you have overclocked the CPU Clock Ratio way above that. To do that my Gigabyte z170 motherboard indicates to set the Uncore Ratio equal to or higher than CPU clock ratio. And they are right ! ;-)
Ideally the Uncore ratio should be the same as the core ratio (as it is at stock values) or (particularly in the case of overclocking) higher than the clock ratio to not constitute a bottleneck. On my Intel i5 6600K I set the Core at 46 (4.6 GHz) and the Uncore at 49 (4.9 GHz) - yes, much higher than the Core! I tested it stable on a 2H Prime95 Blend test up to Uncore 52 and could probably go beyond that value but the overall performance drops after 49, so that's what I use.
To measure performance I measure the time it takes for the system to complete the Prime95 800K test on the four workers. Setting the Uncore ratio at 49 rather than 40 shortens the time by some 7 minutes (from 48 min. to 41 min.). Getting 7 minutes shaved off on 48 is getting 14.5% of raw processing (computational) performance gain! It does not change the Temp. and Power significantly from 40 to 49 (topping at 84 C max under 26 C ambient and 104.5 W) although I had to up VCore from 1.355 V to 1.390 V to ensure stability. The stability of the PC (BSODs, hanging, etc.) is also much greater, in fact rock solid (never had any trouble ever since). It is so good that I really feel it.
Games that would usually get the 4 cores at (for example) 96-98-100-97%, now leave them at 83-85-93-84%, further showing the overall gain in CPU performance. THIS IS ABSOLUTELY FANTASTIC !!! ;-)