Mother board. Since I’ve started a small FAQ about servers I’ll continue.., I’m going to tell a little about mother boards. Properly speaking, server mother boards are similar to usual mother boards but differ a lot from desktop boards – they can have one, two or four processors and the same number of memory banks. Naturally there is no slot for video card. There is always simple VGA, ports and controllers; there is often onboard SCSI.
   Server standard of mother boards, in contrast to those of desktops, means higher level of electronic components safety and their mounting. Any hardware component of a server is tested in a thermal cabinet as this component will have to work 24-hours for years… This high quality and safety determine high price; the simplest server mother board costs about 400 dollars.
Server memory is also non-standard. Common Kingston modules cost three times more as they contain a special microchip for errors correction, it is called EEC. This small add-on helps to increase safety of the memory in several times.
   Hard disks. You might have already guessed that server hard disks also differ from standard. For usage in server SCSI disks or new SAS interface disks are recommended. Briefly, they have a considerably higher degree of safety, better productivity and load processor less. Speed of rotation is 10-15000 turns as against 7200 of standard hard disks; as a result they have smaller size and higher price… for example, 72 Gb disk costs 170-250 dollars. So, I buy an average mother board Supermicro  PDSM4+ with SCSI controller onboard for 500 dollars, processor and 4G of ECC memory. Such server is supposed to work for a long time, but circumstances can alter cases…
Server processor cooler. This is a single story. There is only 40 mm in height of free space inside 1U case; so, what coolers are used in servers? It’s a rather interesting thing. It is one kilogramme device with copper 8 mm base and copper fins pasted to it. This is not a misprint; fins were soldered formerly but now they are pasted. The bottom surface is of good quality but not ideal. I grind it in with a still hone and benefit three degrees.