XP login slow - disable background preload of programs for quick start

OK, I apologise as this is likely to be the least informative question of the week (month, year)!

Some time ago I found a neat little registry edit to help XP to load quicker by disabling a function which preloads programs in the background ... i.e. gets them ready so that when you open them they launch quicker.

Note this is not the same as programs which ACTUALLY load on startup, I'm not talking about anything in the Start\All Programs\Startup folder or the registry settings in HKLM(or HKCU)\Software\Microsoft\Windows\Current Version\Run

Can't think of how best to describe it, Windows remembers what programs you've used before, so when Windows logs in it preloads them in the background so they'll load quicker when you actually start them.

Not a great description, hence the apology at the start ... sorry again.

That ringing any bells for anyone?

I didn't take a note of the edit at the time, can't remember what it's called, so searching isn't doing me any good.

Hope someone can help an old buffoon.

Thanks,

C.