Ryzen 2700X Idle Temperatures higher after adding more intake fans. Opinions on current temperatures appreciated!

[daniel04894]

Hey guys! I believe it's my first time posting here. Before I go on with my question, here is some basic information relevant to the question at hand:

Case: Phanteks Enthoo Luxe Tempered Glass
Motherboard: MSI X470 Gaming M7 AC
CPU Cooler: Corsair H110i (not sure if it's the GT, or GTX version. I'm inclined to think it's the GT)
Replaced the stock Corsair fans (SP140L) with four ML140s in push-pull configuration.
My CPU Cooler is set up as Exhaust

Old Fan Setup:

Intake:

Front: Two 140MM, 74.5CFM each
Bottom: 1 140MM, 74.5 CFM

Exhaust:

Rear: Stock Phanteks Fan (I believe this one is 68.9CFM)
Top: Two ML140 (the ones on the radiator for the H110i), 97CFM Each.

Intake fans always set to max speed, Exhaust fans set by PWM based on CPU speed. Pump is set to "Extreme" (maximum speed) at all times.

Case pressure positive most of the time, except when the exhaust fans ramped up to max speed.

Fan Profile for Exhaust: 50% @ 30 degrees, up to 100% at 70 degrees. (A little aggressive, considering these CPUs are fine up to 85 degrees)

Previously: Idle temps would drop as low as 29.2 Degrees, temperatures under load (10-15 minutes of Prime95) would go up to 62-63 degrees.

One thing that bothered me slightly was that the bottom fan is right under the two front intake fans. not sure if that matters, but it's something. They are where the HDD cages are normally located.

Because of how the Enthoo Luxe is designed, the bulk of intake air was focused around the lower half of the motherboard and the PSU area. That is, from the GPU and upwards (CPU area) there is no direct intake air going over those components.

I made a very simply, yet effective mod to install a fan in the area where the 5.25inch bays are (where your CD drives go). Since that area does not have a fan intake, I used one of the fans I had removed from the Corsair AIO unit (SP140L, 113 CFM), since the high pressure would allow the fan to hopefully pull air in better than a regular one. This intake fan is not set to run at max speed, instead I have it set to work by PWM (they are really loud when maxed).

If you are curious about my mod, I'd be happy to post pictures! It was extremely simple to do, and worked amazingly well. What you need to install a fan there is most likely something you already have. Let me know if you are interested.

New Fan Setup:

Intake:

Front: 2 140mm Fans, 2 @ 74.5 CFM,
5.25inch Bays: 1 140mm Fan @ 113 CFM (max speed)
(Total 3 fans on the front of the case)

Exhaust: Same as before.

Theoretically, with now having positive pressure inside the case, and fresh air blowing directly towards where the AIO fans pull their air to cool the liquid, temperatures should be lower. However, there is an interesting discrepancy.

I have been watching my idle temperatures and they haven't gone lower than 33 degrees. However, when running Prime95 for as long as 30 minutes, my temperatures under load did not go past 59.62

I am not overclocking this CPU, instead just letting XFR2 work its magic. When under load by Prime95, speeds are usually between 4050-4100 across all 8 cores, with it dropping to 3925 for briefs periods of time.

Please note I am using everything in default mode, with Control Mode set to "Auto" (Going to test Precision Boost Overdrive and raise the limits on EDC and TDC Later)
Lastly, why would it drop to 3925 when temps are so low?

I have both CPU power connectors attached to the motherboard (I know it does nothing, call it placebo?)

What are your thoughts? Sorry for the long post, and thank you in advance!

 

[prince_xaine]

With more intake vs. exhaust, you create positive pressure inside the case. This means you are pulling in more air than can be exhausted, which can actually cause heat to become trapped inside the case as the cool air is heated by your components. It's best to make it as even as possible, to create a neutral pressure inside the case.

EDIT:
To add to this, your original temps were actually spot on, especially for a Ryzen Processor. The goal is to have the idle temps be equal to or less than 10C higher than the ambient temperature. So if it's 68F (20C) you should be seeing a maximum of 86F (30C) while idle. But those new temps could be within the margin of error.

 

[daniel04894]

With more intake vs. exhaust, you create positive pressure inside the case. This means you are pulling in more air than can be exhausted, which can actually cause heat to become trapped inside the case as the cool air is heated by your components. It's best to make it as even as possible, to create a neutral pressure inside the case.

EDIT:
To add to this, your original temps were actually spot on, especially for a Ryzen Processor. The goal is to have the idle temps be equal to or less than 10C higher than the ambient temperature. So if it's 68F (20C) you should be seeing a maximum of 86F (30C) while idle. But those new temps could be within the margin of error.

Thank you very much for your reply. I've been doing a lot of changing around, and to be honest would prefer to keep at least slightly positive pressure inside the case (dust prevention and such).

I think I might get rid of the stock Phanteks fan for exhaust, and install a beefier fan back there (perhaps the 2nd Corsair SP140L? Although that might be too much. My front "modded" fan is probably not doing the full 113CFM it's rated at, considering it's pulling air through cracks on the front of the case)

I just tested Precision Boost Overdrive. Raised EDC and TDC to the maximum allowed (168 and 114 respectively) And raised PPT from 140 to 160.

When stress testing, all cores run between 4050 and 4225 MHz, maximum temps seem to go up to 62 degrees.

I'm fairly new to the 2nd Gen Ryzen, so I don't know how good 4.2GHz across all cores is. Is that decent?

Also, I noticed that XFR raises voltages to 1.44-1.46 during stress testing, which I reckon is a bit high. I haven't touched any settings at all except raising the aforementioned limits. Is there any chance that XFR will throw more voltage than the CPU can safely handle?

EDIT: Idle temps dropping as long as 30.75 with ambient temps at 70F.

Go figure. Something else that irks me is how, without using the PC, the temps jump up 10 degrees in Ryzen master from time to time, only to drop right back down.