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(Need Help) New Rig i7-8700k, Asus z370-e, gskill trident z 3000mhz. Have some important questions.

Sep 14, 2018
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Hi every one, i am really lost like never before. New rig with those specific specs:
i7-8700k, Asus z370-e, Gskill trident z 3000mhz.

First of all i want to up my RAM frequency from Default 2133mhz to 3000mhz,
So should i use XMP and then try to lower the RAM voltage? Or just let XMP do he's thing.
XMP = Profile 1 my ram goes to 3000mhz at 1.353v. My cpu core ratio also goes from "Per core" to "Auto" even if i chose NO to the notice that intend to enchance my CPU performance.

Second thing, i want to undervolt my i7-8700k who it's running at 1.248vcore during stress test.
Should i only play with vcore manual offset or adaptive offset? Also should i lower down the other voltage related to the CPU at the same time or let them at "Auto" and finally MCE on or off for optimal undervoltage.

So i want some answers because i did a lot of research on the internet and i can't seem to find anything that goes well together and suitable. Every one have different opinions or answers. One say's to do it the other say's to not. This got me so lost i don't even know what to touch in bios any more.PS: everything its updated even the BIOS to the latest official drivers.

Thanks in advance for every one who wants to help me, i can understand that i sound like a big noob even if i know some things. If this thread frustrate you just don't respond please....
 
Solution
1.248v is pretty low to start with and I would go adaptive pegging it at 1.248 max...though you might get away with 1.2v flat which would be more than good for power saving and longevity of the CPU...though anything below 1.3v will not impact your power usage or the life of this CPU especially in adaptive/offset mode...it's beyond minimal in the grand scheme of things for a 8700K. I needed a High LLC which is load line calibration and stops the voltage drooping meaning lowering itself...really only required in overclocking but also useful in undervolting.

Finally as larrycumming say, this CPU is made for overclocking and just some insight in that it will do 4.8GHz all core overclock with a simple Multiplayer change to 48 and nothing...
1. overclock cpu first , enable XMP after you find a stable OC, 1.35V is normal for overclocked RAM

2. OC with manual mode first, find stable voltage settings, switch to adaptive mode, in adaptive mode set max turbo voltage to the voltage you used for manual mode

3. on asus boards you can set LLC to Level 5 (1-7), it seems to work well for my OC
 


why would you want to undervolt a stock CPU ? you get plenty of power efficiency by Auto mode alone with Asus EPU enabled.

your system wont run at stress testing levels for everyday use anyways. just leave everything auto for stock.

besides, why would you pay for a 8700K without overclocking, just buy i7-8700 only 65W tdp, or OEM i7-8700T

 
1.248v is pretty low to start with and I would go adaptive pegging it at 1.248 max...though you might get away with 1.2v flat which would be more than good for power saving and longevity of the CPU...though anything below 1.3v will not impact your power usage or the life of this CPU especially in adaptive/offset mode...it's beyond minimal in the grand scheme of things for a 8700K. I needed a High LLC which is load line calibration and stops the voltage drooping meaning lowering itself...really only required in overclocking but also useful in undervolting.

Finally as larrycumming say, this CPU is made for overclocking and just some insight in that it will do 4.8GHz all core overclock with a simple Multiplayer change to 48 and nothing else and it will run 4.8GHz at around 1.248 to 1.278v

Second finally..... on RAM, it is better to leave it at the stock XMP setting for the 3000MHZ and for the voltage...though if you really wanted to lower that then set XMP first and then start lowering RAM voltage in super small increments and test to see how low you can go below 1.35v

I suppose undervolting can be as fun as overclocking!!!!
 
Solution
eventually you'll get to that optimum performance per power consumption state, you can do benchmarking instead of system stressing to test your manual speed/watt parameter, you don't need 5GHz all cores to play solitaire or most of the time you're on idle state.
 
Thanks every one you are very helpfull, i think i will do 4.8 ghz and go as low as i can on the vcore another question should i also lower the other cpu related voltages like SB or PLL? Some people says to put them at 1.1/1.0V. Also i wanted to undervolt because this CPU it's a hot chip so why not get the same performance with lower temps. I do a lot of 3D & Video rendering so yeah lower temps will help for the life span of my CPU.
 
You can choose individual OC profile, if your video editor can take full CPU speed and core count then yes OCing CPU is the only way, however, AFAIK, most video editors favor CPU speed instead of core count, so I'd let CPU and motherboard run on it default setting, on CPU render work, you should try enable multi core enhancement (MCE), set voltage related to lowest, test stability, if somehow you stumble to BSOD, screen freeze, then return it to auto,

As other suggested, setting RAM to it highest speed could help overall performance. You shoud consider Geforce card if you use Premiere and AfterEffect.
 
Got it undervolted to 1.088vcore, high peak 1.120vcore. Works really well after some test stressing also my cpu its 15-20C cooler ( i will try others stress test softwares ). I have an gtx 1080ti so im good onto the GPU.

Thanks every one.