AX850 / AX750: clarification about fan starting strategy

Hallo to everyone,

I'm a silent maniac, so I would require from Corsair a technical clarification that helps customer to better understand these excellent products (AX750 & AX850 PSUs).

I'd like to know which are exactly the parameters that make fan start in Corsair's AX750 & AX850.

I mean: temperature? OR load? OR A mixture of these two factors?

Yes, but wich mixture? And wich parameters exactly?

Reading many posts in this forum did not clarify the question. I'd need a technical and definitive answer (only for example: fan starts depending on temperature, when temperature is more than 40° inside the PSU; the same happens when load is more than 300w... or something similar ;):).

From page product here - tab Overview and Specs:

• The AX850's Hybrid Silent Fan Control technology offers three modes of cooling, depending on the load level. This includes a fanless mode of operation (0 rpm) up to about 20% load, a quiet, low fan speed cooling mode for typical loads up to around 50% load, and a higher performance cooling mode for more demanding loads.

•An ultra-quiet 120mm double ball-bearing fan delivers excellent airflow at an exceptionally low noise level by varying fan speed in response to temperature

Question: Is it LOAD or TEMPERATURE?

To better understand: I think these two PSUs are fantastic products, but I guess this technical matter is not so clear.

Thanks.

FR

PS: please forgive my imperfect English language :-)

The fan doesn't turn on until you've hit 20% load. Between 20 and 50% load it's at a set speed.

After 50% the fan speed will increase based upon the load. If the temperature requires the fans to go faster than they already are then they will (assuming the speed's not maxed out of course).

Thanks very much for your answers. :-)

So this would be definitely the truth and correct technical explanation, wich I try to summarize:

- Fanless Mode => active when PSU output is below 20%

- Quiet Mode => active when PSU output is between 20% and 50%

- Cooling Mode => active when the PSU output is above 50%; based upon DC loading and ambient temperature conditions

So, I can understand that:

- under 50% load, it all depends from load

- above 50% load, it dependes from load and temperature variations

=> Is this correct?

=> another final question: in Quiet Mode, the cooling fan runs at very low RPM: which is this fixed low speed? for example, 400 rpm, 600 rpm, or similar?

You are correct frupoli. I am not too sure about the exact rpm under the various conditions, but if you send an email to ramguy@corsair.com with your question, we may be able to get you an answer.

I wrote to them today.

Is this the only way to have this info?

Wouldn't it be possible to have this info in this forum, coming from official Corsair mod? ;):

Thx.

PS: I bought Corsair AX750 two days ago :biggrin:

Ok, I will wait for an answer.

Thx to you in the meantime :o: