be quiet! have risen to the challenge of Quad Core processors and SLI monsters to produce a feature packed unit with enough juice to power even the most power hungry PC. It's unlikely you'll ever need 850 watts of power but having a beast such as this will mean future system upgrades are well covered. be quiet! offer a generous 3 year warranty as standard adding to the lifespan. The bottom line is you won't be upgrading this power supply for years!