What is Spread Spectrum in the BIOS?

kcarrim,
Do you have a wireless card built in to your motherboard? I ask because spread spectrum (at least as I know it...) is a form of wireless communications in which the frequency of the transmitted signal is deliberately varied resulting in a much greater bandwidth than the signal would have if its frequency were not varied

hope this helps.

kcarrim,
Dug around a bit, if you are talking about the "Spread Spectrum Control" function and not just "Spread Spectrum"...that slows the system down and it should always be disabled.

As far as what it actually "is" ...
Spread spectrum makes the signals running on your motherboard less agressive so that the EMI generated are standardized...I suppose if you are having problems with inteference then leave it on..though it will cause a performance hit

It’s for reducing EMI (electro magnetic interference), so if your computer is interfering with your radio, TV, or cordless phone, you might want to enable it to see if that helps, but be warned, it is known to sometimes impact system performance negatively, so you don't want to turn it on if you don't need it.

The following taken from
http://www.adriansrojakpot.com/Speed_Demonz/BIOS_Guide/BIOS_Guide_02d.htm

Which is just about the most definitive bios guide i've found so far.  Always worth a look for any bios related enquiries.

Spread Spectrum

Options : Enabled, Disabled, 0.25%, 0.5%, Smart Clock

When the motherboard's clock generator pulses, the extreme values (spikes) of the pulses creates EMI (Electromagnetic Interference). The Spead Spectrum function reduces the EMI generated by modulating the pulses so that the spikes of the pulses are reduced to flatter curves. It does so by varying the frequency so that it doesn't use any particular frequency for more than a moment. This reduces interference problems with other electronics in the area.

However, while enabling Spread Spectrum decreases EMI, system stability and performance may be slightly compromised. This may be especially true with timing-critical devices like clock-sensitive SCSI devices.

Some BIOSes offer a Smart Clock option. Instead of modulating the frequency of the pulses over time, Smart Clock turns off the AGP, PCI and SDRAM clock signals when not in use. Thus, EMI can be reduced without compromising system stability. As a bonus, using Smart Clock can also help reduce power consumption.

If you do not have any EMI problem, leave the setting at Disabled for optimal system stability and performance. But if you are plagued by EMI, use the Smart Clock setting if possible and settle for Enabled or one of the two other values if Smart Clock is not available. The percentage values denote the amount of jitter (variation) that the BIOS performs on the clock frequency. So, a lower value (0.25%) is comparatively better for system stability while a higher value (0.5%) is better for EMI reduction.

Remember to disable Spread Spectrum if you are overclocking because even a 0.25% jitter can introduce a temporary boost in clockspeed of 25MHz (with a 1GHz CPU) which may just cause your overclocked processor to lock up. Or at least use the Smart Clock setting as that doesn't involve any modulation of the frequency.

Thank you for the input. There seems to be a lot of people out there who has no clue what it is or what it does!

My mainboard manual only states that this should be disabled for better performance. I have Asrock K7S41GX and i am doing a bit of overclocking.

I read an article where the person stated that Spread Spectrum Control is used for cpu cooling. How true is this?

Cool! That is what i thought!! Thanks for all the comments.