Warning, long reply:
Cheap PSUs often cause problems for other hardware in the computer. Yours seems to use an old model even if you just bought it and I would highly recommend replacing it with something of better quality. One of the main things going for hgiher quality PSUs is that they are much safer, both for you and your components. While I doubt your current PSU is one of these, some very bad PSUs are even known to explode... Never skimp on the PSU quality.
More common issues that a cheap PSU can cause:
Bad load regulation, which means it does a bad job of keeping its output voltages near where they should be when the power load varies (12V, 5V, and 3.3V for the important power rails).
High ripple, which means it does a bad job at suppressing AC voltages on the DC outputs caused by the 50/60Hz power line noise and by higher frequency internal switching components. This is especially bad in that it can cause crashes or performance issues in moderate amounts. It can also cause issues if you use integrated audio instead of a discrete sound card.
Also, when poor quality PSUs do fail, while most don't explode violently, they do often fail in short circuits that damages other components in the computer. They tend to have very short warranty periods for a reason: the companies who made them know that they probably won't last long because they made them as cheaply as they could. A lot of cheap power supplies don't even conform to required standards, lie about it, and lie about how much power they can safely output. Just check out pictures of burned PSUs. It can be ridiculous and if you had it long enough for it to build up dust before it fails, then it can even be a fire hazard.
I can't tell you for certain which of these and other problems your PSU actually has because I can't find a professional review of it, but just looking at its specifications does not give a good impression at all. The fact that it is only rated for 220V input means at the last that it is probably a unit with passive or no (edit to fix broken sentence) power factor correction, which is another issue that is not even allowed in modern PSUs anymore because it causes problems for the AC power line coming into the PSU.
Fortunately, there are several companies that actually care about their reputation a little and you can find some decent quality power supplies at reasonable prices.
The best cheap power supplies are often from Seasonic, Antec, EVGA, and Corsair, in order of best to slightly lest best of quality for PSUs in the $30 to $60 USD range. If you live in another country, then I don't know what exactly is available to you, but if you give me a list of anything I can try to help you more.
Some other companies with good or great quality units include XFX, Super Flower, Rosewill, Be Quiet!, and SIlverstone.
Companies to always avoid: Raidmax, Logisys, Ultra,
One basic thing you can do to see if a PSU is at least a more modern n is to look at its power deliver for 3.3V, 5V, and 12V, rated in amps (A). The 12V rail (or rails if there is more than one) should have a higher current rating in A. Ignoring the fact that the specs page for your PSU is completely messed up, what I can only guess is a translation issue, we have this tidbit:
3.3V/14A, 5V/30A, 12V/20A
Which tells me without looking at anything else that this is an older design because the highest current rating, the number with the A, should be on the 12V rail. Older computers uses more 5V and 3.3V power, hence the higher rating on the 5V rail in your PSU. Regardless, like I said before, the 20A rating means it is rated for up to 240W of power on the 12V rail which should be enough for your system. So, your PSU may already be defective or the specifications might be exaggerated. Also, I just noticed that the web page for your PSU specifications is dated 2008, so I'm completely convinced that the PSU, while you may have recently bought it, is actually about nine years old.