When my pc is downloading a page from the internet, I find that when I try to do something in the background that involves the mouse (click on a file to request it, try to paste info into a file,ect.) I most often have to click several times before the clicks do anything.I only began noticing this over the past month or two, but it could be that it was always like this. (Pentium 75, 32Meg RAM). I suspect that this might be happening because I have the modem set up as COM 2, which I think has a higher priority IRQ than COM 1. The mouse will work after several clicks, even while the page is being downloaded. Is this because I happen to click the mouse when the serial port buffer is empty? I guess having a PS2 mouse would solve this, since the IRQ is at a higher priority level, but I don't have a PS2 port. If I'm right about this so far, I guess if I moved the modem to COM1 and the mouse to COM2 this might fix this annoyance. Also, I don't understand why after I click the mouse, I can't just wait for the result, instead of having to keep on clicking the mouse. If an interrupt isn't serviced right away, does it just disappear? Can someone please comment on any of this? I don't know how much, if any, of what I have written here is accurate. Brad Britton PCBUILD: http://nospin.com or [log in to unmask]