[SOLVED] Lowering GPU Temperature

Dec 16, 2020
20
3
25
Hello!

Link to my system [link]

I am looking for some advice about a cooling upgrade. The reason I want to add more cooling fans is to reduce my GPU temperatures (maximum at 80°C and 100°C for hotspot/junction).

Current Fan Setup:
  • Front Fans: 2x LL120's [link] as intakes [Total = 0.6A]. Connected to a fan header called "CHA_FAN" using an extension cable [link] and a Y splitter [link].
  • Top Fans: 2x ML120's [link] as exhausts through the radiator [Total = 0.438A] . Connected to the H100i pump [link] but not sure what powers it.
Question 1: Are all fan headers 12V and 1A unless stated it is not?
The motherboard has the following information: link. The "+5V" on "CHA_FAN" is throwing me off whether or not "CHA_FAN" and "CPU_FAN" are the same (12V and 1A). Is this just to indicate that it's 5V PWM fan friendly? The two LL120's I currently have running off of the CHA_FAN is fine - even though Corsair say LL120s have a range of "7 to 13.2V".

Question 2: Do SATA provide a maximum of 1.5A?
I made this assumption based on information from the information I found around the Internet

Question 3: Are the ML120s and H100i pump powered by the CPU_FAN, USB header, the SATA connection, or a combination of some/all of them?
Now that the two questions above are done, time for the main question, that depends on the answers for question 1 and 2 as they will affect maximum current. Basically, the H100i has 7 connections required to make it work [information from the manual, pages 5 and 6 or 10 and 11]:
  1. iCUE USB cable: connects the pump to the motherboard (via a micro-USB cable) to a USB header [link]
  2. 3-pin pump tach cable: connects to CPU_FAN header (1A maximum - depends on question 1)
  3. SATA cable: power pump cable connects to a SATA (1.5A maximum - depends on question 2)
  4. 2x RGB Connectors: to connect and link the included fans RGB's to the H100i
  5. 2x PWM (4-pin connectors): to connect and link the included fan's to the H100i
What I understood:
  1. iCUE USB cable: for iCUE (software) related elements (i.e. controlling the fans, pump and RGB) and for possibly powering the pump. Last time I forgot to plug this in and the system refuses to get to BIOS which is why I made the assumption that this is the power cable for the pump.
  2. 3-pin pump tach cable: purely to get the pump speed and that's it. Doesn't use any power.
  3. SATA cable: to power the the fans only
  4. 2x RGB Connectors: to control the fan's RGB lighting
  5. 2x PWM (4-pin connectors): to connect and link the included fan's to the pump
Based on the information above, I assume that the fans are powered by SATA and the pump is powered by the USB header. Is that correct?

If the pump is powered by USB, I could use a Y splitter on both of the 4-pin PWM connectors. In theory on iCUE [link], I will be able to control each pair of fans individually with different fan curve profiles - one looking at the GPU temperature and one looking at the CPU temperature. Fan #1 will be the top fans (ML120s) and Fan #2 will be the bottom fans (need to buy them). I just need to make sure the summation of current does not go over 1.5A! So, I can have 1.062A headroom with the current assumption.

However, if the pump is also being powered by SATA and not by the USB header, I will have an unknown amount of headroom and will require a fan hub [link] to not take any chances - unless I use two Noctua NF-F12 [link] since they are 0.05A each (I currently have one of two).

Question 4: Will a dual 60mm be worth it to further cool the system down?
Here's where I plan to install them, if it fits: location. I believe that spot is originally a pump/reservoir for water-cooled systems

My Plans
Intended Configuration [image]:
  • Top: 2x ML120s as exhausts. Connect to a fan hub.
  • Front: 2x LL120s as intakes. Stays connected to the CHA_FAN if it outputs at least 0.6A. Connect to a fan hub if it's not.
  • Bottom: 2x 120mm fans as intakes. Connect to a fan hub.
  • Rear: 2x 60mm fans as exhausts. Connects to the CHA_FAN if it outputs less than 0.6A. Connect to a fan hub if it is.
Alternative Configuration:
  • Top: 2x ML120s as exhausts. Y splitters if H100i pump is not powered by SATA. Into a fan hub if it's not.
  • Front: 2x LL120s as intakes. Stays on the CHA_FAN if it outputs 1A. Into a fan hub if it's not.
  • Bottom: 2x new fans as intakes. Y splitters if H100i pump is not powered by SATA. Into CHA_FAN if it is less than 1A, else into a fan hub.
What would be the best configuration? Feel free to suggest one if the above two are bad.

That's it. Thank you for reading it all if you did.

Edit 1: added my system at the start
 
Last edited:
Solution
1| No.

2| The SATA power plug provides a maximum of 4.5A.

3| The pump controls the fans, the SATA power input provides the power and the USB port allows control via iCue.

I think you're overthinking this. You also forgot to mention the specs to your system in all the text. I personally think you're fine as is. The issue might be that the GPU is just the hot headed one and the cooler can't do much about it, so fans won't help either, if the cooler isn't good.

Lutfij

Titan
Moderator
1| No.

2| The SATA power plug provides a maximum of 4.5A.

3| The pump controls the fans, the SATA power input provides the power and the USB port allows control via iCue.

I think you're overthinking this. You also forgot to mention the specs to your system in all the text. I personally think you're fine as is. The issue might be that the GPU is just the hot headed one and the cooler can't do much about it, so fans won't help either, if the cooler isn't good.
 
  • Like
Reactions: Nickamus
Solution
Dec 16, 2020
20
3
25
1| No.

2| The SATA power plug provides a maximum of 4.5A.

3| The pump controls the fans, the SATA power input provides the power and the USB port allows control via iCue.

I think you're overthinking this. You also forgot to mention the specs to your system in all the text. I personally think you're fine as is. The issue might be that the GPU is just the hot headed one and the cooler can't do much about it, so fans won't help either, if the cooler isn't good.

Thank you for reply.

1. As the saying goes: Don't fix something that ain't broke. I'll leave these fans alone - still need to hear back from Corsair about the blinking RGB light on one of them.

2. That's more than I expected

3. I suspected as much :) Thank you for confirming :D

When I bought the 5700 XT I knew the temperature baggage that comes with it. Just hoping adding a fan or two changes things andante someone in the forums would have some sort of experience will :p

I might buy a Y splitter just to test it out since I do have a spare Noctua.

Thank you again :)