My monitor have no signal dell optiplex 740 desktop

SOURCE: My Dell Optiplex GX1 will not boot. The Monitor shows no signal.

check whether ur ram is working or not. remove the cpu side door and remove the ram from the ram slot and clean it using a eraser gently and fix again it back and power ur pc on and check it

SOURCE: Problem power supply dell optiplex 740 blinking

hi,
this is probably a no power/nopost problem here is a helpfull link
http://tinyurl.com/d4t55m

further queries are welcome
if you think my solution was helpfull please do rate me

SOURCE: No signal to monitor / Beeping

Listen to the pattern of beeps, or look at the back of the computer to see the pattern of the diagnostic lights ( 4 lights just under the keyboard/mouse connectors) and check out this site to see what they mean:
Beep Code Meanings
Diagnostic Light Meanings

Mandeep Singh

• 1184 Answers
• Posted on Nov 09, 2009

SOURCE: my dell optiplex gx270 can not display to a monitor

Hi,
You can visit the following link
http://support.dell.com/support/edocs/systems/opgx270/en/ug/solve.htm#1177038

click on the option
Video and monitor problems

Thanks for using Fixya
Proton

SOURCE: Dell Optiplex 740 Desktop Desktop Computer i

http://www.fixya.com/support/r4282412-find_no_post_diagnostic_information_dell
A solid amber power LED indicates a problem with the motherboard, or something attached to it. (I've seen a bad mouse cause a no post before) Disconnect all cables except power, turn on system see if any LED change. If using a UPS, connect power direct to the wall. If still no change, open case, remove any expansion cards, try again. If still no go, disconnect power cables to all drives, try again.
If still no change, then replace the motherboard