i5-7600k Undervolt settings Asus Prime z370i Noctua NH-L9i NF-A9x14 vs NF-B9 PWM(Redux)

botlebruiser

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Apr 10, 2019
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So I need help with two issues/questions. To make a long story short, I swapped out my i7-8700k/Asus Prime z370i mobo/cpu setup for my girlfriends i5-7600k/ Asus Prime setup. I had a lot of trouble with keeping this cpu cool with the Noctua LH-9i. When I swapped out the motherboard/cpu's I also went back to the NF-A9x14 fan that came with the Noctua cooler. Currently I am using the clear DanCase side panels with 6mm spacers to offset the window off the chassis by 6mm. So I used aluminum spacers between each mounting hole to provide a little more space and to help with airflow of course. I will post up pictures in a few hours.
So I am currently running an i5-7600k/Asus Prime Z270i with a stock Noctua NH-L9i cooler setup. I have a Noctua 92mm PWM Redux fan I can switch to if it would help with cooling. I want to try and undervolt this cpu to give myself a little more headroom for gaming. Currently with the fan setting at 100% I cannot run a full Firestrike 3DMark test without the program shutting down do to the cpu getting too hot.
So, with a Noctua NH-L9i with my i5-7600k what is a safe voltage setting or wheres a good place to start with undervolting.
Also, I tried to change it the bios a few minutes ago and I could not figure out how to change the number next to drop down. I changed the dropdown to manual mode.
Edit: *Sorry, this is my first thread. Pics are working finally.








 
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Donut

Trash Compacter
Mar 15, 2019
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35
I don't have experience messing with your particular motherboard or with Asus' settings for Intel motherboards in general, so some of the names and such may be wrong.

The voltage controls should be available in advanced mode, in the AI Tweaker / Extreme Tweaker menu, under the Tweaker's Paradise section. If you change the CPU Core / Cache Voltage setting to Manual Mode, using the drop down, a few new options should open up to you. One of those should be CPU Core Voltage Override. It defaults to Auto, but you should be able to click the box and type a number into it. Once you've clicked on the box, you should also be able to increase or decrease the voltage value using the up and down arrow keys (in steps of .0625V, I think).

I undervolted my 2400G about a year ago. My strategy was something like this:
  1. Run Prime95 on all cores for a few minutes while you have a monitoring program (e.g., HWInfo) open to log data. After stopping Prime95, check the log from your monitor program. Look for the highest value in the VCore column. For me, that was 1.35, so I made 1.35 my starting voltage.
  2. Go into BIOS. Type the max voltage into the voltage override box. Press the down arrow once to decrease the voltage by the smallest possible amount. Save and exit BIOS.
  3. Run Prime95 on all cores for about 30 minutes. If a crash or an error occurs, the voltage is too low. If a crash or error doesn't occur, go back into BIOS and decrease core voltage by one more step.
  4. Repeat step 3 until an error or crash occurs. Once an error occurs, increase voltage by one step and run Prime95 for a longer period to ensure stability (I did 2 hour runs). If a crash occurs, bump the voltage up one more step, and repeat the longer Prime95 run. If Prime95 does not give an error, this is the lowest stable voltage.
Hopefully that's helpful. I'm absolutely not an authority on this sort of thing, and there's probably better ways to go about this. This worked for me, though.

Edit: I'm not sure the 92mm Redux fan will be any better. It's a bit thicker, but it's max RPM is lower (1600 RPM vs 2500 RPM with the default fan). I don't really know how thickness and max RPM trade off, but I'm guessing they'd perform about the same.
 
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dondan

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Keep in mind the window kit works not very well with >65W TDP CPUs like the 7600k. With Window Kit thin cpu heatsinks like L9i will recycle hot air.

1) Test your temps without any side/window panels attached
2) Did you mount the L9i propper? (Correct screw tightening, correct amount of thermal paste)
3) go on dan-cases.com --> A4-SFX --> FAQ --> How-to improve cooling performance follow the steps (With Window Kit you should consider Long Power Duration 65W or disabling Turbo in UEFI.)

For your special window kit use case the fan duct will not help much, but the redux fan should help because the fan comes clother to the window opening.

If all this will not work: Do not use the Window Kit.
 
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botlebruiser

Caliper Novice
Original poster
Apr 10, 2019
32
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Keep in mind the window kit works not very well with >65W TDP CPUs like the 7600k. With Window Kit thin cpu heatsinks like L9i will recycle hot air.

1) Test your temps without any side/window panels attached
2) Did you mount the L9i propper? (Correct screw tightening, correct amount of thermal paste)
3) go on dan-cases.com --> A4-SFX --> FAQ --> How-to improve cooling performance follow the steps (With Window Kit you should consider Long Power Duration 65W or disabling Turbo in UEFI.)

For your special window kit use case the fan duct will not help much, but the redux fan should help because the fan comes clother to the window opening.

If all this will not work: Do not use the Window Kit.

Update: I undervolted the cpu by .090 volts and got my desired temps for now. The cpu stays below 52c on all 4 cores during 3d mark firestrike and time spy as well as gaming. I played destiny for an hour or so and had good frame rates at 1440p and it stayed below 55c with temps dipping below the 50c mark as well. I and going to make a set of drilled out windows to allow the cpu to breathe. Until them I may just put the metal side panels back on to see how it does. I ran it without any side panel for a long time. But all is well at the moment.

I also have a Corsair SF600

I am currently running a Silverstone SX500-LG which is an SFX-XL psu. I am in the process of deciding between a Corsair SF600 (Platinum) and an EVGA Supernova 650 GM psu. They are true SFX form factor with a little more power. So I can finally order an Asetek 645LT liquid cooler. I am also building my own custom length sleeved cables to get rid of the clutter and free up some space. The liquid cooler should allow me to put my 8700k back in the machine.

Thank you for taking the time to respond and help me out. I appreciate the advice and I will grab my aluminum side panels and put them back on and see if my temps drop at all. I'll report back. The 6mm spacers should have freed up some space for airflow to sneak in the area around the window but I'm didn't test to see if there was any improvement. I might test with and without the 6mm spacers to see if I get better performance with the spacers. I will report all my findings back. Thanks again
 

botlebruiser

Caliper Novice
Original poster
Apr 10, 2019
32
4
I don't have experience messing with your particular motherboard or with Asus' settings for Intel motherboards in general, so some of the names and such may be wrong.

The voltage controls should be available in advanced mode, in the AI Tweaker / Extreme Tweaker menu, under the Tweaker's Paradise section. If you change the CPU Core / Cache Voltage setting to Manual Mode, using the drop down, a few new options should open up to you. One of those should be CPU Core Voltage Override. It defaults to Auto, but you should be able to click the box and type a number into it. Once you've clicked on the box, you should also be able to increase or decrease the voltage value using the up and down arrow keys (in steps of .0625V, I think).

I undervolted my 2400G about a year ago. My strategy was something like this:
  1. Run Prime95 on all cores for a few minutes while you have a monitoring program (e.g., HWInfo) open to log data. After stopping Prime95, check the log from your monitor program. Look for the highest value in the VCore column. For me, that was 1.35, so I made 1.35 my starting voltage.
  2. Go into BIOS. Type the max voltage into the voltage override box. Press the down arrow once to decrease the voltage by the smallest possible amount. Save and exit BIOS.
  3. Run Prime95 on all cores for about 30 minutes. If a crash or an error occurs, the voltage is too low. If a crash or error doesn't occur, go back into BIOS and decrease core voltage by one more step.
  4. Repeat step 3 until an error or crash occurs. Once an error occurs, increase voltage by one step and run Prime95 for a longer period to ensure stability (I did 2 hour runs). If a crash occurs, bump the voltage up one more step, and repeat the longer Prime95 run. If Prime95 does not give an error, this is the lowest stable voltage.
Hopefully that's helpful. I'm absolutely not an authority on this sort of thing, and there's probably better ways to go about this. This worked for me, though.

Edit: I'm not sure the 92mm Redux fan will be any better. It's a bit thicker, but it's max RPM is lower (1600 RPM vs 2500 RPM with the default fan). I don't really know how thickness and max RPM trade off, but I'm guessing they'd perform about the same.


Thanks for your reply. I finally figured out how to undervolt within the asus bios. I had all the dropdowns selected properly. I couldn't change the value for the amount of the offset. It would not let me input a number. I couldn't change it with the arrow keys. I had to use the + and - signs on the number pad of my keyboard. I currently have it undervolted by 0.090 volts and its perfect so far. Thanks for the advice. I appreciate it. As I said above, I'm going to put my aluminum side panels on as well to see if that helps with temps and airflow until I get my 645LT.
 
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