Corrupted Video On NW 6.5 SMB

Hello;

We have installed a new NW 6.5 SMB server, on a Dell PowerEdge Server 2650 Tower, and we had no problems during the install. However when the server was re-booted all the NW console screens are garbled, corrupted, with missing spaces, and missing words, and characters. This effects even the Remote Console screens. When you alt-tab through the screens it actually leaves other characters behind from the previous screen you were on. We tried two different monitors, an older model, and then a New Gateway Monitor. However neither worked. We then installed service pack 2, but this also had no effect. We have been unable to find anything on Novell Support site regarding this, and the only information from Dell is for NW 5.1,which didn't work. Has anyone else seen this issue, and does anyone have any ideas on what to do? Thank you very much for your help,

DS