overclocking 860k, game stutter

dep3kuj · July 27, 2015

Hello guys,

I decided to overclock my Athlon 860k, not much, but I wanted to get it somewhere between 4,3-4,5 ghz. Specs:
CPU 860k

Mobo Asrock fm2a88x extreme 4+

psu coolermaster 600B ver 2.0

cpu cooler xigmantec Loki II

But sadly I couldnt overclock it as much as I wanted. At the moment I am running at 1.325v 4.0 ghz and x18 mult. on the northbridge. Energy saving, C6 is disabled, Thermalthrottle is set to 87.5%.

When I run prime95 at those settings, cpu freq. stays stable at doesnt drop.

When I add voltage and increase cpu multpl., Cpu freq. starts to drop in prime95 (to native 3,5 ghz). I have no idea why. CPU temps do not go over 65C. Every fan works on perfomance mode. Mobo temps are fine as far as I can tell.

With these settings every game expcept BF4 works fine (LoL, Dota2, WoW). In BF4 I get random stutter (like fps drop to 1-2 for 1-3 sec), which happens totaly randomly. If I increase cpu voltage+mult, I get fps boost, but stutters start to happen more often (like 3 or 4 times more often). I believe that it is somehow connected with freq. drop.

I did not increase my northbridge multpl. higher than x20. When I tried to set cpu mult to x4.5, voltage to 1,4v + I've located small fan to cool northbridge radiator, I ran prime95 and after 5 secs my pc shutted down

Any ideas guys?

bronsonp4htdude123455 · July 27, 2015

i have the exact same mobo make sure your saving your profile when you leave bios it can be hard but tell it to force voltage and turn off turbo crank voltage to 1.37 set your over clock to 4.5 ghz or 4.3 ghz if 4.5 wont stay stable I got mine to 5ghz on water to go anything above 4.2 i rcomend water or a darn good air cooler

dep3kuj · July 27, 2015

I always press save and exit in bios, so problem there I suppose.

When I tried 4,3 ghz, It was stable, but cpu always dropped freq. under load, I have no idea why. I would understand the overheat, but it stays under 70C.

And btw cpu-z also shows that voltage is lower, than I setted up in bios. Idk why...

dep3kuj · July 27, 2015

And do I have to worry about northbridge multipl.? Or I should leave it at stock x18 (1800 hz)?

dep3kuj · July 28, 2015

So I've managed to get some stable overclock... As it seems.

What I did is I undervolted my CPU NB from 1.275 to 1.1315, twicked CPU multiplier from x40 to x42 (4,2 Ghz now) and raised cpu voltage to 1,4 volts.

And the most strange thing is that now my cpu does not drop its frequency during prime95 stress test, BUT according to CPUz program my cpu voltage starts at 1,32 volts during first seconds of the test and then drops down to 1.264-1,272 volts (jump in that range). At the same time CPU temps also went down a little. Now I never get over 60C on the core. I have no idea if that cpu voltage difference is bad or not.

I did this test for 20 minutes, everything looks solid.

however, if I rise NB multiplier (without voltage) from x20 (2000Mhz) to x21 (2100Mhz), then my PC does not start at all (black screen).

I dont really now how NB frequncy affects perfomance, but by drammaticaly lowering its voltage I managed to get stable CPU frequency (at least in prime95).

So my questions are - is this test showing that NB voltage was TOO DAMN HIGH by default settings and its lowering leads to cooler VRM and stable Cpu as a result?
Will undervolted NB somehow affect perfomance?
Is this low CPU voltage normal? (cuz in bios it's set to 1,4 BUT it still shows... 1,272. I've also setted CPU voltage offset to -0.85 or something like that to lower voltage in idle I believe, or should I set it to +0 back?)

Do I need to rise NB frequency above 2000 Mhz? Will it add some perfomance? Or I should it as it is and call it a day?