Dell XPS 8300 with amd 7870?

I've been planning to upgrade for some time now and I was just wondering if my Dell XPS 8300 will be able to handle a AMD 7870 card.

The power supply is the 460 watt standard dell one which is also in the newer XPS 8500s and I've seen posts where some users have managed to pull a 7870 with this PSU 0_o.

However, will it work with the xps 8300?