My Windows 7 is very slow now. It takes about 1 min and 30 seconds boot to my desktop. When I installed it, it was very fast. It took about 20 seconds boot to my desktop. I don't have any viruses. What to do? Install Windows XP again?
Slow startups can also be caused caused by device/driver issues.
Have you installed any extra hardware or devices?
Besides removing un-needed hardware or devices for testing there are a few other things you can do.