New motherboard installed but no signal to monitor. Year old graphic card.

[Erchie]

Installed a new motherboard. No signal between PC and monitor.

 

[rhapdog]

We'll need more specifics to be able to truly offer any help.

Before you go to the trouble of answering a long list of questions to assist us to assist you, please try the following things: (I know some of these sound almost child-like to suggest, but I've seen it all so many times.)
1. Make sure your monitor is plugged into the computer properly, and the cable is securely attached on both ends.
2. Make sure the monitor is on and plugged into a power outlet of the proper voltage.
3. Check your memory. If you have more than one stick, take it all out and try one stick at a time, and even try one slot at a time. If one stick works, then try adding a second, third, etc., but only one at a time between boots.

The absolute most common occurrence I have seen in this situation is one or more memory modules either being faulty or simply not seated correctly. Make sure as you re-insert them that they click fully into place, because they don't have to be off by much to keep your computer from booting.

Now, for the questions if the above doesn't fix it:

What are the system specs?

Exactly what all happens when you turn on the computer?
Are there any beeps?
Is there a speaker to provide beeps?
Do fans spin up and run?
Does the HDD or SSD show any activity like it is trying to boot an OS?
Is there both onboard graphics and a dedicated card? Which is the monitor plugged into?

 

[maxwellmelon]

start here
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems

you must go though this guide first before we can help u let us know if you found ur problem or still need help after trying all the items in it. (I got in trouble for helping someone else for this with out sending them though the guide first)
we will assume you checked all these items so really go though the list