problem detecting vga

have brand new macbook pro 13" sl,
hooked vga 1680*1050, , can never detected @ boot,
screen goes blue several times , nothing. have manually unplug , replug display adapter detect. "detect monitors" nothing either.
cable goes through kvm it's same without.
it's not apple brand adapter.
i've been told it's common problem vga, , it's coming macbook. have workaround?
it's pretty annoying.

 

does monitor have other inputs (dvi or hdmi) or limited vga kvm?

 

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