Actually the soundcard is "activated" shortly after the computer POSTs.
If there is a configuration problem with any hardware in your system, you will often see windows "hang" temporarily during boot up. The clicking noise you're hearing is most likely the hard drive (it better be). When the hard drive stops and everything seems to freeze for a bit...windows is trying to initialize a device. If a device is misconfigured, the system will often hang for several seconds (10-30) or hang permanently.
The reason I suggested the legacy driver is that you claim the system works fine except for the annoying bootup. I recently worked with a Live! and had problems getting the legacy driver working (and eventually disabled it because it's useless).
Check your device manager and see if anything isn't working. (right click on my computer and select properties)
If everything is fine, it could just be the effect of bulky drivers on your underpowered system.
Yes, the order in which you install PnP devices is important because the BIOS will assign IRQ's based on slot position. There are many things that could go wrong here, and you should consult your manual. Often times PCI slots are shared. I noticed tonight on an Asus motherboard that it's setup such that PCI slots 2 and 4 are shared, as are 3 and 5. On my Abit BE6 slots 3 and 5 are shared with the Highpoint controller which is kind of a pain.
But alas, we're going into to much detail when we're not even sure if there's a problem. If your certain that everything is working fine, then don't worry about it. The speed at which windows will boot is very much dependent on your hardware.
Slackmaster 2000