How to access the boot menu or BIOS on MSI?

Hello,

I retrieved an old computer that I would like to convert into a LAMP server. However, I need to access the boot menu to tell it to look for the CD instead of the hard drive... and it's impossible. I've tried the F11, F12 keys (since the motherboard is an MSI), F9, and Delete... but nothing works. However, the keyboard is functioning and is recognized (by Windows 98), moreover, it's a PS2.Configuration: Windows Vista
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