What power supply comes with X51 R2?

Hey, I currently have the X51 R2 and I'm not sure if I have the 240 watt or 330 watt power supply, I'm thinking of upgrading my graphics card soon and you need to have the 330w power supply but I'm not too sure which one I have.

Processor: i5-4470
Graphics Card: GTX 945
Ram: 8gb