Generally PCI-E clock speeds are of little help when overclocking.However,sometimes upping the frequency slightly will help with over all system stability.Playing with the PCI-E bus frequency should be left to the serious over clockers.Unless of course you can afford to burn out your system and replace it as needed.I personally have seen no benefit from changing the PCI-E frequency,so I decided to leave it at 100mhz.I had more luck when I changed voltages on my hypertransport bus and memory and cpu frequencies.Goodluck.
AMD X2email@example.com TOLEDO
EVGA NF4 SLI MB
2X EVGA 7950GT KO IN SLI
4X 512MB CRUCIAL BALLISTIX DDR500
WD300GIG HD/SAMSUNG 250GIG HD
ACER 22IN WIDESCREEN LCD 1600X1200
THERMALTAKE TOUGHPOWER 850WATT PSU
COOLERMASTER MINI R120
The nforce fan on a NVidia board would be the fan cooling the northbridge.
The aux 2 fan should be a case fan connected to the mobo but there is no way it is spinning 30,000 rpm, so nvidia monitor isnt reading it right.