I have used soooo many psu's I lost track.
if the gear is pure asic and needs 12.0 to 12.4 volts server psus are better.
the best server psu with 1 fan mod is the ibm 2980 not the ibm 2880 it gets true platinum 93% as long as you stay under 2600 watts and can do 2900 watts
Right now as I type I have one running 2 avalon 7's
the next best server psu is the dps 2500
it will give true gold 91% at 2000 watts and can do 2300 watts
of course both are a shit ton of watts.
I have used 50 different ATX psus
and some can not do 75% of rating 24/7/365 some can
Since I have 13 pc's mining alt coins with gpus all use plat or titaniam atx at about 60%
Rosewill quark plats are good for 60% 24/7/365-------- great sales right now a 550 watt for 69.99
http://www.newegg.com/Product/Product.aspx?Item=9SIA07234S8693modular and will mine 2 rx 480 gpus
evga p2's are good
evga t2's are better but cost a lot
evga g2's are good
seasonic prime titanium are good but cost a lot
I melted seasonic plat
I melted seasonic gold
corsair plat AX Series AX760 good
all silverstone titanium are mediocre they dont quite get the titanium rating unless you are 50%
that is the 600 700 and 800 models
At the moment when I get an atx I look for a good deal on evga p2 and or rosewill quark
When I go for servers I like dps2500 and ibm 2980
I buy Finksy/j4bberwock or optimizer breakouts