i just order a new tv receiver with component output, I was just wonder what is the lowest resolution for component?

I was not aware that any TVs had component output. Are you sure that you do not mean component input?
Component inputs normally include at least 480i, 480p, 720p, and 1080i.
You can probably find the users guide for the model you have ordered on the TV manufacturers website and that guide will list the specific component information supported.