58c is pretty damn good for the CPU's
Generally AMD under a load runs between 56-74c and stays fairly stable....mine runs 58-60 and have nt experienced any bad issues...and out of the 100's of systems I have built that is normal.
as far as cooling fans...check out OCZ Technologies or Cooler master..however OCZ Tech mainly built for those overclocking machines and gamers...they work wonderful in servers =)
you have to tak into account the core technology of the processors...there are certain thoroughbred CPUS from AMD that run a hell of alot hotter... hell when the 2000+ came out it ran so hot that ou literally got 3rd degree burns when you touched it on accident or whatever.... they do run hot...depend on the core tech of them and what you have your core temp set at and if you are in anyway overclocking them inadvertantly or purposely.
hmm no load? I would consider some better cooling...somehow I got the impression that was while using the machine and I did not read careully you were looking in BIOS...my bad....
those temps are a little high at an idle.
check out ocztech and coolermaster for some better cooling.
nother thing you might look into if you havent already...most "stock" cpu heatsinks and fans come with a very low end thermal tape to disapate the heat between surfaces...try to get yourself some thermaltake thermal grease....believe it or not that stuff does wonders