LED question

[supra33202]

http://www.case-mod.com/store/product_info.php?cPath=33_37&products_id=74

5mm Blue LED - 2200 MCD

Emitting Color: Blue
Wavelength(nm): 470
Lens Type: Water Clear
Typ. MCD: 2200mcd
Typ. Voltage: 3.5v (4.0v MAX)
mA: 20
Viewing Angle: 15
Lead Length: 27mm

Is it possible to power up the LED with 3.3V? And if I power it with 4.0V (MAX), will that shorter its life?

[RobStyle]

I have been screwing with LED's for the past few months.
From what I have gathered, 3.3v isnt a problem.
Just the light may be a little more dim than.
Anything higher than the average voltage will shorten its life,
but, make it brighter.
Also,
dont forget LED's will probly live longer than you can use them.

I am running one superbright red & one superbright amber to light the top of my case off one 330ohm resistor.
Have had them running for alooong time now and have noticed no color or brightness change.

330ohm resisitor is running in the positive yellow power.
I think red positive you will need 100ohm resistor.