fan speed changes, computer slows down

Two weeks ago I had a problem with my TV tuner sound, and updated the nVidia RIVA video card driver. The sound came back on but I am having problems with performance. The cooling fan pitch goes up and the computer slows down...the cursor lags behind the mouse, pages take a long time to come up, it takes several seconds to click on a scroll bar and make it work. When the pitch goes back down, everything speeds up again to normal. I have reinstalled the drivers, changed the hardware acceleration, cleaned up my disks, and have very few programs running in the background-- all to no avail. Gateway has been of NO help whatsoever.
PIII 550, 256 RAM, 32 MG NVidia RIVA TNT, 20 GB HD,DVD, CD-RW, STB PCI TV Tuner

1. RE: fan speed changes, computer slows down
lbyard Feb-07-02 07:00 PM
In response to message 0

>The cooling fan pitch goes up and the computer slows down...the cursor lags behind the mouse, pages take a long time to come up…
So, maybe the CPU is overheating and you need a new fan, or something (cable?) is getting in the fan? Larry
Pentium® III Processor Active Thermal Management Techniques (http://developer.intel.com/design/intarch/applnots/273405.htm):
“The simplest implementation to control the temperature of the processor can be constructed using the temperature sensor and the PIIX4E southbridge to throttle the processor… However, if the duty cycle of STPCLK# is not sufficient to cool down the processor, the operating
system or System Management software must reprogram the duty cycle to slow down the
processor. This may involve inserting interrupt routines”.

2. RE: fan speed changes, computer slows down
Pamela Stine Feb-08-02 04:11 PM
In response to message 1

Thanks Larry:
I cleaned the fan blades which were very dusty, as was much of the interior of the case. It appeared to be flowing freely, nothing in the way. The change in pitch can go up and down within a few seconds or take several minutes. Usually it is when I go to a new website, start a new game, or try to open an application that the higher (slower action) noise occurs. But then again, sometimes it just does it by itself while I'm sitting contemplating my navel. I don't know about the CPU overheating as I get this phenomenon just as often when I boot up in the morning as later in the day. The powersupply fan has always been very loud - on continuously, you can hear it out of the room so perhaps it is a suspect part and needs to be replaced as you suggested. Shall I replace the entire power supply, upgrading from 200W or just the fan? Is it something a novice could do?
Again, thanks

3. RE: fan speed changes, computer slows down
lbyard Feb-08-02 07:09 PM
In response to message 2

>The powersupply fan has always been very loud - on continuously, you can hear it out of the room so perhaps it is a suspect part and needs to be replaced as you suggested.
This probably has nothing to do with the computer running slower. However, no power supply fan should be that load and the supply probably needs to be replaced. I was referring to the CPU fan. Larry
>Shall I replace the entire power supply, upgrading from 200W or just the fan? Is it something a novice could do?
One would normally replace the entire supply if the power supply has a standard formfactor, etc., which it probably is if it is a Gateway. It is not a difficult job. I would get a 300 watt supply so you can use it for a future upgrade. Larry