Any assistance will be greatly appreciated, thanks!
I was playing a game and suddenly, with no warning, the computer forcibly powered down. I figured it was overheating, so I cleaned the filters, not that they were clogged or anything, and when I pushed the power button it failed to power on. Upon closer inspection, and after unplugging the unit, it turns out that the one fan with lights in it powers on for about a quarter of a second and then nothing. In addition to this the power supply makes a high frequency sound, not unlike that an old monitor or old TV makes. This sound persists until the unit is unplugged. Further attempts to power on fails, until the unit has been unplugged.
I would try a better brand power supply, such as antec, corsair, pc power and cooling, seasonic, ocz or enermax. Your old ps is low end; surprised it lasted this long. You need about 750w; newegg had a corsair 750w for $89.99 after rebate, or check craigslist.
That is an option but if you still not sure whether it is the power supply i recommend you bench the board always a helpful thing to do trust me. And if you are looking for a robust product to replace your current PSU, i always Gigabyte ODN, sure they pricey but they never fail just like all Gigabyte products.