@amiga2000:
Here's a few short rules about any SVGA monitor and Amiga.
- 15kHz support is out of the question (native modes through native scan rates). Good luck finding a modern monitor that supports it nowadays.
- Scan Doublers can work ONLY if your monitor can sync down to 30kHz on the horizontal scan side. I find it that most monitors that go as low as 31kHz simply can't work reliably or don't work at all.
My advice to anyone thinking about using a scan doubler with their Amiga is to look for a monitor that does 30kHz lowest horizontal scan.