Quote Originally Posted by fgw View Post
i did this mod and soldered a switch to my ddc. i can now switch between ddc1 and ddc2 modes. the difference is 3900rpm vs. 4500rpm and in my loop about 1.8liter/minute vs 2.25liter/minute which is a 25% increase in flowrate.
running at 4500rpm the ddc is noticeably louder but it's not that bad at all.
on the other hand, the increased flowrate does not much to my cooling performance. think i'm on the lower end of flowrate anyway. may be there would be a difference in cooling performance if i could up my flowrate to 4liters/minute ...
1) How'd you know the exact RPM between the 9w & 18w settings?

2a) Do you have some damper / gel pad / decoupling system in place for your pump?

2b) Would you say the DDC2 setting is still quieter than a 900-1000rpm 120mm fan? Or if you can't reference the noise level to a fan, then maybe with some other component in your system (e.g. what's louder or quieter than the DDC2 setting).

3) Could you fill me in on how to create a switch for the DDC? It's probably really simple, but never took an electronics class in high school =/

Thanks.