How To debug why the server freezed

Hi, there is a method for know why the server during the normal work, without any register into /var/log/messages, freeze? I use a standard kernel 2.6.11-1.27_FC3smp on a i686 hp proliant 110 and I have rebuild and use a conexand driver for a USB ADSL Modem (http://accessrunner.sourceforge.net/driver.shtml) Also I use the linux-atm package ( linux-atm-2.5.0-0.20050118.2) The server work great for many hours, then freeze. Please, suggest me some kind of method for know what is the problem and what component caused the server freeze. Many thanks -- Dario Lesca <d.lesca(a)solinos.it&gt;