FX 8320 / ASUS M5a99FX pro R2 Voltage

As the title says im trying to get the lowest voltage possible out of the stock 8320 on a asus m5a99fx pro r2. Its my friends, he doesnt want it overclocked, but i set cpu & NB voltage control to manual from offset and manually set cpu voltage to 1.325v. When i get into windows at idle it sticks at 1.320v and once prime 95 runs it jumps to 1.344/1.356v. With the offset voltage when i had it down to 1.344v it stayed within that as a max, and when i tried going lower with the offset it jumped up higher. Is this Prime95 that is doing this or what?
 
Solution
turn LLC down to it's lowest settings.
and turn down cpu current capacity to it's lowest settings as well; swap cpu power phase mode to standard while you're at it.

yeah, that's because of how piledriver works.

piledriver has something called "voltage droop", when it's under load the voltage it's drawing actually drop. LLC and cpu current capacity combat that droop in 2 ways.

LLC provides more power to prevent the droop in voltage
CPU current capacity allows the chip to suck down MORE power then it's set to draw when under load.

If you want to remove the drop in voltage happening in prime, start to bump llc up a bit. when you find the sweet spot, it will keep the chip right around the set vcore under load and at idle. The bump up in vcore you were seeing was caused by the cpu current capacity being set higher then 100%

Those are both overclock tools, and if you have no interest in overclocking, can basically be turned off to drop temps and power usage.
 
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Hate to hijack a thread but.... how dafuq did you manage that clock on the 8320? That's amazing.
 


it's a golden chip, got lucky... I haven't actually tried to hit 5.3ghz on my new motherboard... on account i sorta broke the one i hit 5.3 on. (granted a sabertooth should be able to hold silly overclocks like that pretty well, but my rule of thumb is don't overclock what you can't afford to break)

I knew i could push this chip hard when i hit 4.5ghz 100% prime95 stable with stock vcore. Unfortunately this is what's called a "low leak" chip.

I'll explain~

Piledrivers come in 3 flavors...

High Leak
Normal
Low Leak

High leakage cpus can take huge voltages, and generally bleed off their excess heat pretty effectively, basically a high leakage chip (in theory) makes a better overclocker. ALL of the 9xxx series cpus amd releases are high leakage chips. This chips don't get very hot for all the power shoved into them.

Normal are moderate overclockers... these piledrivers typically will get you to the piledriver voltage wall... and if you got a really good cpu cooler you might get over it. but generally 5ghz is a pipedream on one of these unless you have a custom cooling solution. basically their cap is around 4.8ghz... they might get you to 4.9... and if you have a mediocre cooler they won't get you past 4.5ghz... if you're lucky.

Low leakage are a blessing and a curse... low leakage hit high clock speeds with very little vcore. however they tend to be nearly impossible to cool effectively. These are the chips that will overheat on a stock cpu cooler at stock settings. at the same time, if you have a robust enough cooling solution, and you're a little lucky on the quality of the chip, these babies can hit very high clocks on insanely low voltages.

Most 8320s are low leakage chips... it's how AMD bins them... same with the fx 6300. Now the 6300 hit 5ghz left and right, because it's a lot easier to cool a 6 core then it is an 8 core. Now typically you can tell in the bios what type of chip you've got by the stock vcore. Low leakage chips typically will have a stock vcore around 1.32v, where as high/normal typically will be around 1.38v.

What really was the lucky part for me, was this chip is a VERY golden one. meaning it needs very little vcore to do anything. The first thing i did when i started overclocking is see how far it would go on stock vcore (cause i saw the very low vcore it was sitting on). it loaded into windows at 4.6ghz (which is quite high, typically, you won't get past 4.4ghz on a piledriver at stock). it even could pass a light stress test, though i wouldn't call it "stable" at 4.6. it is rock solid at 4.5 though and stock vcore... though it's also HOT. I have a corsair h100, it's a pretty good cpu cooler, and it really doesn't do a great job even at stock keeping it amazingly cool. But think about that. this is a chip with a stock clock speed of 3.6ghz... and i was hitting 4.5ghz at the same voltage.

well it needed a modest bump of voltage to get to 4.8ghz... and that stabilized well, though temps were getting iffy. 5.0ghz was the top i could get with my cooling and passing a stress test; its stable at 5.0ghz, and in the winter that's what i keep it clocked at... but it's summertime in phoenix and the ambient air is a bit high, so i keep it at 4.8ghz. Though 5.0ghz needed a LOT less vcore then most piledrivers need at 4.8ghz... (it's stable at 1.48v on the vcore at 5.0ghz). That 5.3 was me just pushing to see how high i could get it. I was able to load into windows, run the cpuid verification, and upload it at 5.3ghz... and 1.55V on the vcore. but i wouldn't even begin to call it stable... i probably need 1.6 on the vcore to stabilize it. you'll notice the temps too, are very high for doing basically nothing. So no... without an exotic cooling solution, i doubt i'd be able to ever actually use it at 5.3ghz.

so yeah... i got lucky with a great chip... not the best piledriver out there (i've seen better)... but pretty good none the less.
 
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You need to get that thing in an overclocking competition under sub-zero. I dread to think what kind of records it may be able to break.
 

BrandonCSLC

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Nov 18, 2013
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I have my Fx 8320 at 4.4Ghz with stock voltage of 1.32v. It could run prime 95 without crashing at stock voltage but it failed at gaming. So I set the offset to .05 and then it ran smooth as silk. No more crashes. I can play Crysis 3 with SLI 4gb 770's around 80-100 fps.

Pretty amazing thing to squeeze an extra 1000MHz of performance out of a chip with a jolt of .05v.