More details are needed for troubleshooting purposes.

Is it a Radius pivot? What are you running the monitor from? Onboard video or a Radius PrecisionColor nubus video card? If an ordinary monitor running from a Radius Nubus card, then presumably RadiusWare would be all you need, and it is easily found. If a pivot or from onboard video, you may be staring at a blank screen for a few weeks still. Some Radius monitors were cantankerous.

Try Gamba for help on this.