Hi,
Dell Studio 1535 cooler(fan) always on, even if the system is not warm up. Plus mouse and keyboard work slowly.
shut down computer, wait (5h.), but still the same. Checks the system load and temperature - all the norm.
What happened? When you say the fan is always on... are you speaking of the CPU fan or the fan for the power Unit?CPU fanIf you are talking about the fan kick-in, you might have a faulty fan controller or you UPDATED the BIOS from A05 to A06 which lowered the temporary kick-in by 10 degrees.

The speed of the fans can be controled on some motherboards and software linking to it, if you have issues with it running too fast check your BIOS settings / Fan Control Software. Some overclocking software will also NORMALLY increase this or temperature monitors.

Check your fans are clean from DUST and there's nothing sitting on them like a wire, this will make them have more noise and have to work harder. This includes the heat sink getting cogged with dust. Also make sure the fan isn't DAMAGED or off balanced.

I found this - Dell Studio 1535 fan problem: http://www.youtube.com/watch?v=ISIcmEOJt88
Looks like a common problem with that fan...

As for the mouse and keyboard working slowly are you using USB connection or PS/2? Quote from: lolalola on March 16, 2010, 07:25:45 AM

Hi,
Dell Studio 1535 cooler(fan) always on, even if the system is not warm up. Plus mouse and keyboard work slowly.
shut down computer, wait (5h.), but still the same. Checks the system load and temperature - all the norm.
What happened?