i can not use my external monıtor help :(

[erdaras]

hii i tried with a few external monitors but all the same. when i open system preferences>displays i can see color lcd and my external display and i can select a resulation but there is nothing on the display besides NO SIGNAL!!. what should i do?? i'M using a mini displayport to dvi adaptor and a dvi to vga adaptor

[spinnerlys]

Have you tried a miniDisplayPort to VGA adapter, as the problem might be the DVI to VGA adapter.

If that doesn't help either, let your machine be checked at the nearest Apple Store or Apple Authorized Reseller.

[waw74]

check out the section of this page (http://www.datapro.net/techinfo/dvi_info.html) about "dvi formats"

the only reason a dvi to vga cable works is the vga signal is normally already in the connector, but the MDP to dvi adapter doesn't have it there.