I quite agree with you - I don't think there is a widely accepted or standardized guideline of the vNB. Being on air - I think I'm being a bit more conservative. I think Cob and some others on Water are up much higher then I'm at.
My NB was 1.58v for 4ghz, and is now down to 1.52v for my 3.9ghz day-to-day clock.
I just have an 80mm fan sitting on top of my graphics card bowing air onto the NB. Not even sure if I need it.
Q9450 @ 4ghz + ASUS P5Q Deluxe on H2O
2x36gb Raptors RAID 0, 4gb OCZ PC2-8000
x64 XP Pro, x64 Vista and x64 Ubuntus SMP goodness
Q6600 @ 3.8ghz + Abit IP35 Pro on H2O
XFX 8800GS Alpha Dog, 4gb OCZ PC2-8000
x64 XP & x64 Ubuntus SMP goodness
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