Hi Stephen,

You can try the below methods and see if it works for you:

Method 1: Alter the Hardware Acceleration

You can try changing the hardware acceperation to medium and verify it.
1. Right click on empty space on desktop.
2. Go to Screen Resolution.
3. Then click on Advanced settings and click on the tab "Troubleshoot".
4. Set the hardware acceleration to medium. (here you will get the option only if your Video card support its).

Method 2: Uninstall the video card drivers
 After uninistalling, restart the computer and let windows install the generic drivers and then check if the HD videos play fine.
It's best to let Windows install drivers automatically. Occasionally, Windows might not be able to find a driver for your device. If this happens, you might want to check the manufacturer's website for a driver or update for the device, or try installing any software that came with the device.

Method 3: Uninstalling and Reinstalling the Windows Media Player and Windows Media Center:

Uninstalling the Windows Media Player:
1. Go to Start and in the search type "Turn Windows features On or Off".
2. Click on "Turn Windows features On or Off".
3. Browse to the Media Features and uncheck the mark in front of Windows Media Player.
4. Restart the computer

Reinstalling the Windows Media Player:
1. Go to Start and in the search type "Turn Windows features On or Off".
2. Click on "Turn Windows features On or Off".
3. Browse to the Media Features and place a check mark in front of Windows Media Player.
4. Restart the Computer.

I hope this helps.

Regards,
Lokesh