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I would only use them as a last resort.Blower fans usually are quite noisy, especially when spinning fast. The 4020 fan does not specify but the 4010 says it is 24-26 dBA at max speed of about 5000rpm. For comparison, an Noctua 40x10 fan generates 20 dBA at max 5000 rpm.But, I think the weakest link is its airflow volume. I expect it to be around 0.07-0.09 m3/min at max rpm. For comparison, an Noctua 40x10 gives about 0.14 m3/min.Having said all these, I suppose when you really need ventilation at tight spots, these blowers should still be useful.
I would only use them as a last resort.
Blower fans usually are quite noisy, especially when spinning fast. The 4020 fan does not specify but the 4010 says it is 24-26 dBA at max speed of about 5000rpm. For comparison, an Noctua 40x10 fan generates 20 dBA at max 5000 rpm.
But, I think the weakest link is its airflow volume. I expect it to be around 0.07-0.09 m3/min at max rpm. For comparison, an Noctua 40x10 gives about 0.14 m3/min.
Having said all these, I suppose when you really need ventilation at tight spots, these blowers should still be useful.
