xerxesaria

Distinguished
Dec 19, 2012
165
4
18,685
Hi.

I have a motherboard:
- Asus Rog Strix Z490-e Gaming.
My case is:
- be quiet 500DX

The case has already 3 fans. I have purchased 2 more case fans. This motherboard has only 2 fan connections. So, for now my set up is:

2 exhaust fans via a y-splitter
2 intake fans via a y-splitter

As for the 5th fan, I asked Asus directly if I can connect it to the CPU_OPT fan connector. They confirmed that it is possible.

But what I haven't heard from them back is:

Is the CPU_OPT meant for exhaust or intake fans? Or doesn't it matter? What is best?

Thank you.
 
Solution
....

Is the CPU_OPT meant for exhaust or intake fans? Or doesn't it matter? What is best?
...
It's meant for a CPU fan as noted. Any CPU should always need a fan for cooling so it's not uncommon for a motherboard to refuse to POST if it doesn't detect a fan on that header to prevent burning up the CPU. It's also frequently monitored to trigger alarms if the fan speed falls too low.
Sep 30, 2020
4
0
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And there is a difference as to what fan ports you plug into. for example when trying to set a fan curve you dont want your exhaust system fan plugged into the cpu opt slot. use sys fan ports on your mobo to run your intake/exhausts and the cpu for whatever cooler you use, whether its air or water, it wont matter. but the cpu fan curve will be accurate and easier to control. especially if youre overclocking.
 
....

Is the CPU_OPT meant for exhaust or intake fans? Or doesn't it matter? What is best?
...
It's meant for a CPU fan as noted. Any CPU should always need a fan for cooling so it's not uncommon for a motherboard to refuse to POST if it doesn't detect a fan on that header to prevent burning up the CPU. It's also frequently monitored to trigger alarms if the fan speed falls too low.
 
Solution