Instead of 3Ddiag, try using nv_check.sh.
I've got a newer version here
Although you should probably get it quite soon (i.e. tonight), because my entire site will be going down for like 3 weeks over Christmas break starting tomorrow morning. Power will be off here in the dorms, so the site can't be up while I'm gone. If you don't get it, you can probably find it somewhere else, but it might be slightly misleading if your distro uses devfs.