- Microsoft has issued a Knowledge Base article which says that if you install Windows XP SP2 on a machine with an AMD 64-bit chip your computer may repeatedly re-start. The workaround, said Microsoft, is to remove Windows XP SP2 from your computer. The problem happens if you install hardware that uses the mpegport.sys, you've got an AMD 64 bit chip, and you've enforced the NX flag, also known as no execute protection, on a machine.