Motherboard issues

What is the make and model of your MOBO?

Does it have an onboard video card? If not you will have to purchase a separate video card.

You cannot connect a monitor to a serial port.  

System specs?

Okay my mobo is MSI P43 C51 and my friend told me I need a gpu. So I plugged in my new xfx 5750 1g and it turned on but the monitor didn't turn on or show anything. So I put in my old graphics card PNY 7600 gs 512mb and it worked and loaded fine. My ati xfx 5750 is brand new and I bout this mobo because it has a x16 express 2.0 slot and it worked with my E8500 that was in my old computer. So I don't understand why the monitor want turn on. I'm using a Corsair tx650w, I thought that was enough wattage for the gpu. Please help me.

Thanks for the help but I figured it out. For some reason when I put my xfx ati 5750 in and plugged my monitor in the HDMI port it wouldn't work. So I tried the DVI and it worked perfectly. I guess it's not set at defualt to work with HDMI.