Although DELL and IBM are nice most of our servers are custom builds built in-house. The reason why we prefer such is that we have more control over the hardware that goes into the machines, in addition the DELL servers that we have, if something breaks and we replace the parts we loose the warranty, the standard dell service agreement is within 1 business day, they come to the datacenter and fix it, sometimes one business day is one day too long, neither we or our customers can afford prolonged downtime.