No Display in ASRock 775i45GV Motherboard

Try cleaning the RAM as shown in the image below:

also you can try resetting the CMOS, here's how it's done on your motherboard:

CLRCMOS0 allows you to clear the data in CMOS. The data in CMOS includes system
setup information such as system password, date, time, and system setup parameters. To
clear and reset the system parameters to default setup, please turn off the computer and
unplug the power cord, then use a jumper cap to short the pins on CLRCMOS0 for 3
seconds. Please remember to remove the jumper cap after clearing the CMOS.

The location of the CLRCMOS0 on the motherboard can be seen on the image below. (labeled no.10)



If problems persist. Replace the RAM. Hope this helps.

First you need to try removing ram and connect again. It normally occurs .. for me too.

And please comment here on update, if it works and if not..