Safe to run XY PCB w/ monitor disconnected?

Specifically with Atari -- Star Wars and Major Havoc, is it safe to run the
PCB with the monitor completely disconnected or can it cause problems?

I'd like to work on the games using a scope for the output, and disconnect
the monitor (at least the power) until I get the boards working correctly.

The reason I ask:

http://www.geocities.com/SiliconValley/Horizon/2253/vectors.html

indicates that the regs output needs to be clipped.

Thanks

---
Bret Pehrson
http://www.vaps.org/members/nv/bret@classicade.com.html
mailto:bret@classicade.com
---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.