You sure about that model number?
This page: http://www.dell.com/lt/business/p/dell-p2414h/pd#TechSpec
Suggests it doesn't have HDMI at all.
Yeah that's the right model - I meant I'm using a DVI to HDMI cable
Then just use the DisplayPort from the Graphics card?
How when I've only got a VGA spare - Is their another way I can do it
If that is the correct monitor, then it has the following ports.
Connectivity
1 Digital Visual Interface connectors (DVI-D) with HDCP
1 Video Graphics Array (VGA)
1 DisplayPort (version 1.2a)
4 USB 2.0 ports ( 3 downstream ports, 1 upstream port)
This is why VincentHanna is suggesting you use a DisplayPort to DisplayPort cable.
If your monitor doesn't have a DisplayPort connector, then the model that VincentHanna posted the link too isn't the correct one.