When you got error F4D41436, you were using PowerDVD v4 or higher to play the DVD disc, right?
If so, the reason is that some video cards with TV-Out function must have the TV-Out function disabled before powerDVD v4 or higher will work. It is disabled by powerDVD itself (apparently to prevent piracy) & this error message is related to TV-OUT being enabled.
I suspect you are correct about safe mode being the reason for this error in that case. One work-around for this, is to use powerDVD v3 instead.
You are also correct in assuming that safe mode is the reason for the lack of audio. In safe mode, only the essential drivers are loaded & as audio isn't considered essential, the sound card drivers will be one of the ones that aren't loaded at startup.
As there appears to be a noticeable difference in video performance when you start Windows in safe mode, I'm wondering whether your problems are being caused by one of the drivers. In particular, either the Nvidia driver or the chipset (AGP) driver.
Can you tell me which Nvidia driver you have installed? i.e is it the driver from Nvidias website or from the CD that came with the video card? Also, what version is it?
Do you know which chipset you have? As the cpu is an AMD k6-2 (socket7), I suspect the board may have either an ALI chipset or Via MVP3 chipset. Can you confirm this?
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