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Question

Is it normal for my CPU fan or other fans to speed up.

May 4, 2013 2:03AM PDT

Hello again, I'm wondering if it is normal for my fans to speed up like when I restart my computer or if they kind of speed up at random time during rebooting or starting up.

Discussion is locked

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Answer
Yes.
May 4, 2013 2:14AM PDT

It's the new design to have the fans speed or slow on demand. This can really irritate some owners and at first machines had a setting for constant speed. As time wears on, I wonder if that setting is gone.
Bob

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Answer
Typical operation
May 4, 2013 4:14AM PDT

Variable RPM fans are typical install in many PCs now. Understand that cpu even during power-ON are placing an immediate temp difference and the sensor notes that and places fan into high-RPM mode. You may noticed it settles down once the temp "normalizes" or becomes what it should be. Alas, when the temp difference once again rises as in higher cpu demand and reaches the critical level, it kicks-in. That's what it's suppose to do, it no longer maybe a user setting, especially for OEM based PCs.

tada -----Willy Happy

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Answer
It is normal these days, but...
May 4, 2013 11:12AM PDT

most motherboard BIOS chips have several settable options for fan controls, or OEM applications that will allow the used to configure how many fans are used, and how fast they run according to circumstances.
In the case of BIOS settings, you normally get a choice of DEFAULT - normally controlled by internal temperatures, ON - full blast, or USER DEFINE, where you dial in what speed you want it to be.
Most boards from 07 onwards have PWM controls on all the fan sockets, which means that you can balance the airflow though the PC case AND control the CPU fan speeds in relation to the ambient within the case itself.
This is a big help to those of us who run two GFX cards in SLi (or crossfire) mode, where you have a big hotspot over the PCI-E slots, right under the exhaust from the CPU which in turn cools the heatsink of the chipset.
It's all a big balancing act; on the one hand, you want to keep everything within the case reasonably cool, but by the same token you don't want to be using more power (and making more noise) than really necessary.
I hope this is helpful.

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Answer
variable speed
May 14, 2013 4:14AM PDT

Fans now have variable speeds, if not done by your BIOS you can purchase an external fan speed controller.

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Answer
There is no need to worry.
May 21, 2013 5:30PM PDT

hi,

YES....It is normal because when we start the pc the first cpu catches the power. So due to high power fans runs fast and there is also makes some small noise. There is no need to worry.