|I agree of-course that RAM itself is volatile. However there are large capacitors around (inc PSU) which can maintain voltages on the motherboard.|
I had a situation on my now rarely used W98 computer. The Wifi worked fine in Windows until I booted to a Linux Live CD and went online with it. When I went back to Windows the Wifi failed. It could be revived by reloading the Wireless Adapter software.
Someone here suggested that I unplugged the mains from the tower, then held the power on/off button in for about 20 secs after using the Linux CD. When I did so I noticed a quick flash from the light on the tower (which also happens on other PC's).
I powered up again and my Windows Wifi worked immediately. This is still quite repeatable.
Whether it was RAM or some other chip I really don't know but I can assure you that "something" gets stored "somewhere" when you power off, and for a long time too.
I was using a Belkin USB Wifi stick so I suppose that could have been storing the settinga - dunno.
Since that experience I suggested that "discharge trick" on a couple of threads where I thought it had possibilities - it worked on one of them.
More recently when my Win 7 netbook wouldn't start at all I did the same thing to revive it (taking the main battery out too before pushing the power off/on button).
I know this sounds like "magic". I had little faith when it was initially suggested but I'm not making it up.
Always pop back and let us know the outcome - thanks