I'm looking for an AV that has a automatic start up scan every time I turn on my computer. Is clamwin have automatic start up scan?

No. ClamWin is an on-demand scanner, which means that you can scan with it whenever your want. You can do a manual scan of a file, a folder, or the entire computer by right-clicking the mouse on a file, folder, or the C drive. You can also set up an automatic scan at the time you want.

My opinion: Waiting until you turn on your computer to scan for a virus after it gets on your computer, that may be too late--damage may already have been done. Your antivirus should detect the virus at the time it is put on your computer and then quarantine it before it can do anything.

The Clam Sentinel program lets you scan with ClamWin when files are added, modified, or copied on your computer. Clam Sentinel is a free, open source program available at https://sourceforge.net/projects/clamsentinel/ on the web. Sentinel also has a separate scan engine that can detect viruses for which there is no ClamWin signature. If you download it, be sure to read the Simple Guide before installing it.

Regards,