Hi, workingmanx1.
The stock psu is 360 watt 12/16amp psu. I would replace with a larger psu immediately. I have gone through 3 power supplies on my Dell Studio XPS435mt and upon further investigation, small psu units seem to be a trend among computer manufacturers. I don't think this is good. I've heard complains of blue and black screens, complete power failures and weak power flickers which could be the worse. Some from fresh new 435 units.
Electrical current has to be a constant (strong) in order to be safe, if the voltage is too low, electricity has to make jumps from molecule to molecule to connect. What happens when it jumps too often, it will start to burn across the connections. If the burn connections get too wide, it stops because it can't get across. Then your computer is kaput. It's the hardest hardware repair because it's hard to find. It flickers in the end and then complete power failure. If you make your choice to replace your psu make sure it not only has good wattage, but amps as well.
I bought a 500 watter with less than 17 amps and the fan inside it kept ramping up. It was getting hot, then the psu died after 7 months. I installed a larger 750w 64amp psu and it was heating up for unknown reasons but was faithful, worked really well but put out a lot of heat. The bios on the mobo would only allow a certain amount of current to the board, making anymore power unavailable (there have been no bios upgrades for the 435mt since 2009, which doesn't help). I can only guess the power in the psu had nowhere to go.
I removed the 750 watt psu and replaced it with a 650 watt, 52amp psu and the psu heat problem disappeared. I would've choosen a 550 watt psu with more amps except the video card I installed required a 500 watt psu or larger. So in my estimation, I choose the 650w 52amp for adding all additional, peripherals and future components. Here's a psu calculator site you can use to figure your computer with.
http://www.thermaltake.outervision.com/index.jsp
Here's another little bit of information I happen to come across finding this stuff out. Corsair, SeaSonic and XFX contract one company to make their power supplies. They're good units like Thermaltake. So there was an upside to checking power supply units out. The unit I have right now is SeaSonic G-650w 52amp, but I would consider those brands and a few mentioned in the past comments.
Hope this helps,
Wreks