Installing win98SE on a newish PC. Mobo definitely supports ACPI. I know there's a registry hack *after* win98 is installed which causes an Enummeration refresh for ACPI. But what I want to know is: Is there any way to install win98SE to force it to recognise ACPI?

/p j should do the trick, hope this works for you too.

http://support.microsoft.com/kb/186111/en-us

Thanks that's exactly what i was looking for :-)

I think I have been going on some wrong info for a very long time. I was told (years ago) that /p i forces APM mode, and reading the description doesnt help me very much. So what is the real effect of using the /p i switch during installation?

If you look at the MS reference given, you'll see:

i - This switch tells Setup not to report the existence of a Plug and Play BIOS. It is useful on computers that have a Plug and Play BIOS that is not reported in the Machine.inf file

WARNING! on the j (not i) switch: win98se support for ACPI especially on newer mobos is dubious to say the least. I used it last week on a fresh install on a Foxconn Nvidia NF3 mobo. No end of problems with power management. After two days of struggling with the consequences such as no power down, lock-ups with screen savers and many other problems, decided to re-install WITHOUT ACPI: i.e. without using the j switch. Everything is now fine and stable.

Thank you Mr. Spock

That's completely logical.

Yes, but what does that actually mean and what would the real world effect be of using it? Im just curious because I have been mistakingly using that switch for years because I thought it was something totally different.