I finally solved a long-standing problem with my Windows XP laptop.
My CPU would slowly grow to about 15% even when idle. Then a window would pop-up telling me I had 60 seconds to reboot because an RPC service had crashed. This occurred about once a week. Often enough to be annoying, but not often enough to make me dig to find the problem. The crashed "RPC service" was not very instructive, because it's a service used by lots of programs. So clearly some software running on my computer was "abusing" this service.
At first I thought it may have been due to the Intel PROSet/Wireless software running on my computer that was doing something bad with RPC, it turns out the problem was with Nvidia driver software for my Nvidia graphics card. The problems were on my Asus A8JS laptop, under XP Pro SP2 & SP3, with an Nvidia GeForce Go 7700 graphics card, and Nvidia Forceware 163.44 drivers, with DirectX 9.0c.
I found the solution here:
I had to disable the Nvidia Driver service (see detailed instructions below). After that, I've not had any of the symptoms.
This describes the exact symptoms I was seeing (including the 1 minute to reboot):
Apparently, you can shutdown the Nvidia Driver helper without much consequences. There may be some multi-monitor stuff that doesn't work, but you can always start it manually, or re-enable it to start automatically.
Read on for detailed instructions…
You should run the Windows XP "Computer Management" application, so you can disable the service. You can probably find this under Start, All Programs, Accessories, System Tools. If you can't find this, then you can run it "manually" by using Start, Run, then enter compmgmt.msc. If that doesn't work, try Start, Run, then services.msc.
Next, expand the tree to find Services, then scroll down to Nvidia Display Driver.
It probably will show as "Automatic" in the startup column. You want to change it to "Manual". Double-click to get the properties window, then change the Startup type to "Manual".
Click "Ok" to close all the windows, then re-start your computer.
If for some reason you lose some functionality, you can always temporarily run the service by going back to the properties window and clicking the Start button. This will run until your next reboot. Or if you want to permanently turn it back on, change the Startup Type to automatic.