Bovon
03-13-2001, 10:29 AM
Hi guys and gals. I have been reading a lot at many different forums now for about two months, trying to get a handle on which mainboard will be my next upgrade for AMD processors.
After reading many threads, and corresponding with a few ppl that seem to have more problems than most, I have come to a possible conclusion that many of the troubles may be power supply filter troubles.
My credentials. 40 years plus in industrial electronics with trade school / job training.
When converting from AC (alternating current) to DC (direct current) there will be a certain amount of AC ripple or hum left over in the DC output. some ripple is acceptable if filtered very good, and kept at some predetermined limits.
As with anything we buy today, we get what we pay for. Just because a computer power supply says it is a 300 or 400 watt supply, isn't enough. It absolutely must be filtered as good as possible. The cheaper supplies for the most part will not have the higher degree of filtering. Many times they will just get by. AC hum can, and will cause all sorts of problems in a computer. Too much, and it won't even post. bare minimum hum can cause crashes. Just because a power supply is an approved supply found at your mobo or processor site dosn't mean it is a good one.. it simply means it passed some degree of tests...maybe on the low end of their limits. Some of these that passed the tests may be assembled with cheap components that will not last long.
We tend to pay out of the gazoo to get the mainboard we want and the processor & ram...then skimp on the case and power supply. It can be a reasonable conclusion that the power supply is one of, or perhaps the most important part of the system. If the supply fails, so does everything else.
It works like this. When converting from AC to DC is called rectification. The filtering process within the supply can take out almost all of the residual AC component, called 'hum'. As with anything, the filtering can get expensive...these parts cost money...and the ppl that make them must compete with others, so they sometimes manufacture supplies with cheaper parts. Usually, the more expensive supplies will be made better and have the best (or much better) components to filter with.
One simple test to determine if your computer supply is generating 'noise or hum' is by placing an old AM type of radio near the computer. Tune the radio to an unused frequency. (no stations coming in) if you hear hum...this is being generated in the computer supply. You may hear a small amount of hum (ideally you should hear none). If you have no problems, you are probably ok...again...no hum is best. This is just a quick and easy way to test, but does not take in all possibilites. The computer case can diminish the hum from getting outside of the case, so..just because you don't hear any him with the case on, dosn't mean there is none there. Also, this is not the best test. Only instruments can detect the amount of hum, and tell the technician if it is acceptable or not.
On an old machine I used a few years back, I was loosing internet connections every few minutes. One day, I just happened to turn my radio from FM to AM, and here was all this hum. I knew right away what the problem was. I replaced the power supply, and my disconnects went away...
Bottom line. Be sure you don't try to save money on a cheap computer power supply. The problems that can and will crop up are hard to find, and the operating system won't tell you what is wrong, AND...the computer techs at the shops or mobo / processor company won't have a clue...they are not trained electronic technicians.
And yes, I knew I would forget something. When a power supply is loaded down to near its power limits, the current drag from the supply will be too much for the filters, and hum will then creep into the system. The more load, the more raw AC that will be present in the DC output...
Hmmm... I think that covers it, Any questions, I will try to answer, but understand I can't see / test your system
[This message has been edited by Bovon (edited 03-13-2001).]
After reading many threads, and corresponding with a few ppl that seem to have more problems than most, I have come to a possible conclusion that many of the troubles may be power supply filter troubles.
My credentials. 40 years plus in industrial electronics with trade school / job training.
When converting from AC (alternating current) to DC (direct current) there will be a certain amount of AC ripple or hum left over in the DC output. some ripple is acceptable if filtered very good, and kept at some predetermined limits.
As with anything we buy today, we get what we pay for. Just because a computer power supply says it is a 300 or 400 watt supply, isn't enough. It absolutely must be filtered as good as possible. The cheaper supplies for the most part will not have the higher degree of filtering. Many times they will just get by. AC hum can, and will cause all sorts of problems in a computer. Too much, and it won't even post. bare minimum hum can cause crashes. Just because a power supply is an approved supply found at your mobo or processor site dosn't mean it is a good one.. it simply means it passed some degree of tests...maybe on the low end of their limits. Some of these that passed the tests may be assembled with cheap components that will not last long.
We tend to pay out of the gazoo to get the mainboard we want and the processor & ram...then skimp on the case and power supply. It can be a reasonable conclusion that the power supply is one of, or perhaps the most important part of the system. If the supply fails, so does everything else.
It works like this. When converting from AC to DC is called rectification. The filtering process within the supply can take out almost all of the residual AC component, called 'hum'. As with anything, the filtering can get expensive...these parts cost money...and the ppl that make them must compete with others, so they sometimes manufacture supplies with cheaper parts. Usually, the more expensive supplies will be made better and have the best (or much better) components to filter with.
One simple test to determine if your computer supply is generating 'noise or hum' is by placing an old AM type of radio near the computer. Tune the radio to an unused frequency. (no stations coming in) if you hear hum...this is being generated in the computer supply. You may hear a small amount of hum (ideally you should hear none). If you have no problems, you are probably ok...again...no hum is best. This is just a quick and easy way to test, but does not take in all possibilites. The computer case can diminish the hum from getting outside of the case, so..just because you don't hear any him with the case on, dosn't mean there is none there. Also, this is not the best test. Only instruments can detect the amount of hum, and tell the technician if it is acceptable or not.
On an old machine I used a few years back, I was loosing internet connections every few minutes. One day, I just happened to turn my radio from FM to AM, and here was all this hum. I knew right away what the problem was. I replaced the power supply, and my disconnects went away...
Bottom line. Be sure you don't try to save money on a cheap computer power supply. The problems that can and will crop up are hard to find, and the operating system won't tell you what is wrong, AND...the computer techs at the shops or mobo / processor company won't have a clue...they are not trained electronic technicians.
And yes, I knew I would forget something. When a power supply is loaded down to near its power limits, the current drag from the supply will be too much for the filters, and hum will then creep into the system. The more load, the more raw AC that will be present in the DC output...
Hmmm... I think that covers it, Any questions, I will try to answer, but understand I can't see / test your system
[This message has been edited by Bovon (edited 03-13-2001).]