I forgot to add, that even after figuring out your wattage level and then finding you have a model PSU that is X-wattage, it should work. Not always the case. Understand, that better PSU are build with a 80+ rating, meaning they deliver on a constant and stable basis(excludes heat stress) a wattage level of the noted amount. So, if you have a 500W PSU, then it should provide 400W under typical circumstances reliability. However, if your needs are 350W overall on a constant basis, that's pretty close to stressful levels just on needs alone. Should it creep closer like 380W, then it becomes a concern and selecting a 600W PSU will be a better choice for now and later. It just offers better stability as times goes by. As I already posted, HEAT is a killer, as it will reduce the stability and overall wattage output, so a 400W level will drop to 390W(or lower, 15% is typical) and waver. Also, single level designs provide wattage from a single source and offer *all* what they have, they DON"T split the wattage over multiple rails. Dual or multiple rails designs offering lower wattage(per rail), thus the load must be balanced(connections) so they don't exceed that rail output. Again, the load and/or level supported is best under 80+ rating.
Just so you understand clearly, "CHEAP IS CHEAP". You get what you pay for, sometimes the lesson is the lost of the PSU along with other PC devices or components. Plus, all that down time to include frustration of a rebuild/repair.
I hope this helps...NOTICE I didn't mention any brands but cost is higher for better PSUs.
enjoy 2 ------Willy
In case you didn't notice often on this forum and others, having a decent and stable PSU is critical to a good working PC. The PSU is so taken for granted that anyone building thinking only GPU and CPU concerns quickly finds out the hard way, the PSU just isn't capable even if it works may not for long.
Excluding my basic advise and just get a decent brand name and have at least 100W above your needs will do. The more watts, the better IMHO. But how can you tell what your needs are? Simple use a PSU calculator. Google for hits, but below are some links:
Extreme is a pgm. you can d/l for free version. Also, notice the "rail voltage" specs, these provide the "amps" that overall are part of the final picture. Understand, better PSUs cost more to include better components, wiring and cooling aspects. Alas, your PC should be well cooled as well to help exhaust heat build-up besides what the PSU itself can do, HEAT is a killer.