Well, lets get into this.

the less icons and stuff on the desktop, less cpu noise, less work to dram the mouse pointer, its one of the reasons I have a black (windows color) desktop, it eases a lot rendering the icons and switching between apps.

Check your computer ground connection and all stuff connected (on midi ports, lcd screens produce imense noise due to the EL pannel)

Audio connections with poor or damaged cables loose their ground, so check them with an ohmmeter, more than 2ohms and the cable is junk

Optical and laser usb mices produce lots of cpu clocks, more noise

Also a matter of luck with the electricity quality, some suppliers mess with the frequencies on purpose, mostly deviating the power from the voltage a few degrees so things tend to consume more to have the same result, more noise.

ps2 mices don't (or shouldn't) produce any noise, since they are hardware supported in a different manner and IRQ channel.

Change the sound card IRQ line to a different one from the usb IRQ line (right click on my computer, and go to the hardware tab, advanced, change and hard reboot), test several pci slots, check motherboard manual for the pci ports IRQ sharing, physical IRQ sharing with usb or ATA controllers means.. more noise.

I've had lots of problems in my TV network time with first digital audio mastering equipment, pc based 486 DX 40 mhz computer (wavelab) by the time and some Macintosh II, looking into this things should help to solve the problem.

DS, having USB professional sound cards with internal processors, are actually more productive than PCI due to channel latency, check alesis or yamaha for such sound cards.

Hope this helps

Kudos

Might be worth to try this too?

forum.corsair.com/v3/showthread.php?t=75330" onclick="window.open(this.href);return false;

Its about the sound coming from the psu, but...

well i tested it on my 10 years old system
no noise BUT there are 2 sound cards installed

I testen with onboard and creative one and both have no noise. It could be that creative card is cancelling it out for both or it could be that there is just no noise.

I just tried plugging it in ps/2 port. Doesnt work. Is the port not supported or is it my ps/2-usb adapter/

Nah mate,

forget ps2 adapters with a razer, it has specific drivers and internal memory and the shizz... it doesnt work at all...

Like I said, I used to have it, and when I changed to my creative x-fi it went away.

Could be anything else, but seemed like the soundcard. Could be ground too as Tunes mentions, it could have been from the case I changed to