That wattage is low but quality is equally, if not more, important. Here's some food for thought. Power Supply FAQ PSU 101: How A Power Supply Works PSU 101: PC Power Supply Basics How Power Supplies Are Rated
Wattage calculator to get ideas from... Calculator
You can also get tools like this
to determine how much wattage your overall system has to see how much headroom you have left. I suggest not running over 70% of your PSU depending on eficiency.
Lastly, if you power down your computer, and take off your side panel, there's a good chance a sticker will be on the power supply unit itself that has more detailed info about it.