That adapter won't solve the flicker problem unless your software uses the system-friendly Intuition screen opening routines so that you can use mode promotion. And the biggest problem is that the internal scan-doubling circuitry on the AGA chipset is that it slows down terribly when you are using DBLPAL or DBLNTSC.
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The main ones that won't work with that adapter are PAL and NTSC which are the main ones that most software uses.
