I've got a coolermaster cm 690 and it's got slots for 120mm fans but most of the fans I had were 90mm. Is there some loss of efficiency, leaking or poor cooling that will come from not utilizing a 120mm fan for a 120mm fan slot? Right now, my temps are fine. I was going to pick up at least one fan for the side panel next to the video card since I just didn't have enough fans and was considering filling out the other slots that had only 90mm fans but didn't know if it was worth it. Thanks.
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Case fan question
- Thread starter Mnx4
- Start date
Technophobe
Limp Gawd
- Joined
- Feb 25, 2008
- Messages
- 339
If you have a 120 and 92 mm fan that does the same cfm, you will probably find that the smaller fan is louder. Thats why people go for the larger fans at lower rpms.
Well, good news, got the new 120mm Yate Loon's, 70CFM from petra's. Bad news, I was a little special and didn't realize I already had 120mm fans, and the larger apetures were for 140mm fans. Oh well. Now I have less variability in fan speeds and CFM in the case.
Two question though. I'm trying to match the intake to the outtake. Two of the 120mm fans I didn't replace have variable knobs. I've worked the math and placement so the intake is around 291CFM and the output is around 250CFM. Two of the intakes, the bottom and the front panel, have filters. Filters reduce the pull and thus the CFM correct?
Another thing. I started messing with the variable outtake fan in the back. It pulls 110CFM at max and I turned it down a little and noticed the top fans would blow out more air. When it was turned up, it blew out significantly less air. So what could account for that? Diversion of airflow? Or screwing up the pressure in the case? Basicaly just asking if this could be an indication of how to find the "sweet spot" for in case pressure.
Two question though. I'm trying to match the intake to the outtake. Two of the 120mm fans I didn't replace have variable knobs. I've worked the math and placement so the intake is around 291CFM and the output is around 250CFM. Two of the intakes, the bottom and the front panel, have filters. Filters reduce the pull and thus the CFM correct?
Another thing. I started messing with the variable outtake fan in the back. It pulls 110CFM at max and I turned it down a little and noticed the top fans would blow out more air. When it was turned up, it blew out significantly less air. So what could account for that? Diversion of airflow? Or screwing up the pressure in the case? Basicaly just asking if this could be an indication of how to find the "sweet spot" for in case pressure.