I've struggles with 3 different videocards and DOS, and never hot it to simply work like it should. There was always some problem. My last card I tried was an ATI which is claimed that it should work. Well it keeps cycling colors like mad...
In the end, I got really fed up with it and bought an ArcadeVGA. Haven't had time to set it up though (also bought new mobo, proc, memory etc., installing that now). But I trust it will work fine.
Could have saved myself lots of time and iannoyance by buying the ArcadeVGA right away....