to see if there was an actual reason why ppl promote really expensive power supplies besides knowing that they own one. Does it actually cause problems?
Component quality and reliability aside There are a couple of things known as spikes and sags. Both can greatly affect the proper function of electronics. Sometimes spikes and sags are external and can wreak havoc with a cheap power supply thereby putting your computer at risk of damage. Then there are the spikes and sags that are caused by the cheap power supply itself. Depending on the severity of the fluctuations and the tasks the computer is used for the computer may exhibit instabilities when performing processing intensive tasks that place a load on the power supply it cannot keep up with. Conversely if the computer is used primarily for lightweight processing tasks like email, Web surfing, and typical office functions The power supply's shortcomings may never manifest themselves. Do I use a really expensive power supply? Yes. Would I recommend that everyone get one like mine? No. But there are very good reliable power supplies out there that while they cost more that the rock bottom bargain bin junk supplys they are certainly affordable and worth the cost.
You my friend have been lucky. I have seen many cheap supplys that lasted less than a year. I have seen many that when they failed fried parts of the system.
Here is a cheap bargain bin 500 watt supply for $20. Read some of the user reviews on this guy. They aren't very impressive.
http://www.newegg.com/Product/Produc...82E16817159062
Here is a basic Antec unit. Read the reviews on this one. They are considerably better. It costs about $50. I would rather pay $50 now than have to replace it in a year and possibly some damaged parts as well.
http://www.newegg.com/Product/Produc...82E16817371004
Here is something even more expensive. If I were in the market for a 450 - 500 watt unit and I intended to do some very intensive tasks with the computer I would absolutely pay the $70 for that unit but not everyone would need it. I probably would however.
http://www.newegg.com/Product/Produc...82E16817703011
Look if you drop $800 dollars or more on a reasonably powerful system that will be the repository for most of the digital parts of your life, juniors baby pictures, tax returns, yadayadayada... Why would you skimp and stick a 20 dollar power supply in it? That would be like buying a very nicely outfitted SUV and sticking a 4 cylinder yugo engine in it. Sure if you only drive it to the store and back it may make it just fine and the engine might even last a while. Try taking it on the expressway though and there will be problems.
It is your choice. If your happy using nothing but bargain bin supplys then more power to you. However you do a disservice to anyone that you recommend crap supplys to. Sooner or later it is going to come back and bite someone in the ass and it will be your fault.