I've heard that T620 are very quiet in comparison to other dell servers so it's very nice to hear that this machine is comparable to an Optiplex desktop system with respect to noise output. How is your T620 system configured, what equipment is installed inside the chassis like memory; (registered dimms?, size?), hdd; (types?, number of hdd's?), etc?
One downside with servers, if it is a downside at all, is i shut down our T610 over long weekends and some hot evenings and this machine is slow to boot (to Win7 logon )when i bring it up the next business day. Somewhat understandable but annoying nevertheless. And I believe the T620 takes even longer, maybe 4 minutes as i have read in some reviews. Still, if i could get a T620 for the price i payed for my T610, i would ignore this very minor issue and likely make the jump to the T620 
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