PC Peripherals CORSAIR CMPSU-400CX- 400W Power Supply
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Heh. I have used HDDs and dvd writers which ran with 12.8-13V on 12V for 2-3 years and guess what? They're still running now.ROCKFELLA said:and pay monthly installments of high electricity bills, un-explained hdd crashes and system unstability :cool2:
I'm using a VIP 300W dual PSU setup in which the ground on one PSU ahs shorted, so even though the mail PSU supplying power to the board and processor is off, all fans incl CPU fan etc all keep running. its very complicated to explain how assumingly dangerous this is, but I never had any problems with it :|
There are really good + cheap PSUs. not all are good but some are very good indeed. thats what I intend on using, not these sky high priced PSUs.
Its hard to convince someone about PSUs here :noob:
SunnyBoi said:Heh. I have used HDDs and dvd writers which ran with 12.8-13V on 12V for 2-3 years and guess what? They're still running now.
I'm using a VIP 300W dual PSU setup in which the ground on one PSU ahs shorted, so even though the mail PSU supplying power to the board and processor is off, all fans incl CPU fan etc all keep running. its very complicated to explain how assumingly dangerous this is, but I never had any problems with it :|
There are really good + cheap PSUs. not all are good but some are very good indeed. thats what I intend on using, not these sky high priced PSUs.
clown_abhi
Forerunner
I think any1 would be better off buying a POV BD500 for 2.7k rather than going for this 400W. The POV seems better value...
Oh no I pay 10 rupees more electricity bill than what sky-high PSU owners pay! boo hooROCKFELLA said:U or your folks have already paid higher electricity bills since u used that contraption PSU for 2-3 years..... this is what you dont realize
Anywyas i am out of here.
Ignorance is bliss. !!!
it is a tragedy that very few here really understand how a smps psu works, The dynamic nature of a computer system hence a consequence of which the dynamic nature of the power requirements.
more worrying is that not many still dont know how to read and interpret the psu wattage ratings of known good psu manufacturer's. (since cheap ones are just stickers in the truest sense).
it is not a simple arithmatic additions. there are many conditions attached to these figures.
let us consider the ratings of the corsair CMPSU-400CX psu
The Max Rated Currents are 3.3V=20A , 5V=20A, 12V=30A.
and the Max Combined Wattage of 3.3V+5V =130W and 12V= 360W.
What this means is that this psu is rated for providing a max current output 130W on the 3.3V plus 5V combined , PROVIDED that the sum of all other wattages of all the other voltages like 12V, -12V, +5Vsb is 400 - 130 = 270W.
400W being the rated max or total output of all the rails.
130W being the sum of the max current output of the 3.3V and 5V combined.
similarly the max output of the 12V rail (line) is 360W. This means that this psu WILL PROVIDE 360W on the 12V rail but the output of all the other outputs i.e. 3.3V, 5V, -12V , 5Vsb will have to be 400W - 360W=40W at that given instant when the psu is providing 360W on the 12V rails.
here we have to consider the following
a) at no given time will any smps psu provide the max wattages on the different voltage rails (lines) as adverised on the rating sticker.
b)The line that is monitered, controls the microcontroller of the psu. hence it ultimately determines the final outputs (both voltage & wattage)
c) modern motherboards and graphic cards do not use much of the 3.3V and 5V. very meagre usage.
d) many a times the 3.3V is derived from the 5V line, from the secondary side of the switching transformer.
e)The monitered line is sampled thousands of times per second.Depending upon the monitered voltage the psu microcontroller regulates the switching time of the transformer which determines the final outputs.
f) The Temperature of the switching transistors , tranformers, rectifying diodes play a very important role in any smps psu. The efficiency of a psu drops significantly as the temperatures of the above mentioned components rise. drop in efficiency can be 20% or more as the temperature rises from 25C to 40~50C, beyond 50C it is a very steep fall.
This monitered line varies amongst the different chassis (i.e. oem manufacturers) of psu's. some use the 3.3V , some 5V etc...
in short, the smps psu is designed in such a way that it can meet the individual rated MAX Wattages of each voltages provided that the sum of all the other outputs does not exceed the total rated power output of the psu.
The condition or purity of the outputs, the effects of high temperature in degrading the outputs etc .. is a seperate topic hence i am not posting about it.
members here who do not have any clue of the working of a psu should refrain from posting their ignorance, it is like spreading disinformation or false information.
as regards this corsair psu , it is good for a medium level gaming m/c, but the cost imho should be in the Rs. 1800 ~ Rs.2200 region.
E. & O.E.
Typos and Grammatical mistakes are my BirthRight, they are by design. You may ignore them , analyse them, correct them in ur mind, at ur discretion. I dont care.
it is a tragedy that very few here really understand how a smps psu works, The dynamic nature of a computer system hence a consequence of which the dynamic nature of the power requirements.
more worrying is that not many still dont know how to read and interpret the psu wattage ratings of known good psu manufacturer's. (since cheap ones are just stickers in the truest sense).
it is not a simple arithmatic additions. there are many conditions attached to these figures.
let us consider the ratings of the corsair CMPSU-400CX psu
The Max Rated Currents are 3.3V=20A , 5V=20A, 12V=30A.
and the Max Combined Wattage of 3.3V+5V =130W and 12V= 360W.
What this means is that this psu is rated for providing a max current output 130W on the 3.3V plus 5V combined , PROVIDED that the sum of all other wattages of all the other voltages like 12V, -12V, +5Vsb is 400 - 130 = 270W.
400W being the rated max or total output of all the rails.
130W being the sum of the max current output of the 3.3V and 5V combined.
similarly the max output of the 12V rail (line) is 360W. This means that this psu WILL PROVIDE 360W on the 12V rail but the output of all the other outputs i.e. 3.3V, 5V, -12V , 5Vsb will have to be 400W - 360W=40W at that given instant when the psu is providing 360W on the 12V rails.
here we have to consider the following
a) at no given time will any smps psu provide the max wattages on the different voltage rails (lines) as adverised on the rating sticker.
b)The line that is monitered, controls the microcontroller of the psu. hence it ultimately determines the final outputs (both voltage & wattage)
c) modern motherboards and graphic cards do not use much of the 3.3V and 5V. very meagre usage.
d) many a times the 3.3V is derived from the 5V line, from the secondary side of the switching transformer.
e)The monitered line is sampled thousands of times per second.Depending upon the monitered voltage the psu microcontroller regulates the switching time of the transformer which determines the final outputs.
f) The Temperature of the switching transistors , tranformers, rectifying diodes play a very important role in any smps psu. The efficiency of a psu drops significantly as the temperatures of the above mentioned components rise. drop in efficiency can be 20% or more as the temperature rises from 25C to 40~50C, beyond 50C it is a very steep fall.
This monitered line varies amongst the different chassis (i.e. oem manufacturers) of psu's. some use the 3.3V , some 5V etc...
in short, the smps psu is designed in such a way that it can meet the individual rated MAX Wattages of each voltages provided that the sum of all the other outputs does not exceed the total rated power output of the psu.
The condition or purity of the outputs, the effects of high temperature in degrading the outputs etc .. is a seperate topic hence i am not posting about it.
members here who do not have any clue of the working of a psu should refrain from posting their ignorance, it is like spreading disinformation or false information.
as regards this corsair psu , it is good for a medium level gaming m/c, but the cost imho should be in the Rs. 1800 ~ Rs.2200 region.
E. & O.E.
Typos and Grammatical mistakes are my BirthRight, they are by design. You may ignore them , analyse them, correct them in ur mind, at ur discretion. I dont care.
Another thing i forgot to post, related to psu requirements.
i have seen many posts here where members ask for the optimum wattage requirement for their system. This Tip is for them.
First roughly calculate the power requirements of ur system depending upon the components and their usage, i.e. whether extreme gaming or not (most power requirement), the concurrent usage of all the components and their duration of use etc...
there are many sites which have the values for your components, just google for it.
after you get a rough figure in watts for ur requirements then multiply that with root of 2 for nominal usage (not extreme gaming)
for example if your requirements comes to 300W (normal power consumption, not peak requirements)
then you should get a psu with real or true 300 x 1.41= 425W approx. output.
if you have high demand like games , heavy cpu intensive tasks, then multiply that figure of 300W by 2 i.e. 300 x 2 = 600W for peace of mind.
it is always a good thing to keep ample head room in reserve as the peak loads can shoot upto 2 times, momentarily, under certain circumstances. Also as ur m/c requires more power it puts the psu under great stress, this leads to increase in temps inside the psu as well as leads to dip in voltages due to the heavy load.
This generally leads to degradation of the "quality" of the power outputs. if you have ample head room then the psu will not be under so great a stress and the efficiency as well as the quality of the power outputs will be maintained.
Bad outputs can kill ur million dollar graphic card in a very short time.
Also remember that by design an smps provides power just as much as the load placed on it. in other words if your running requirement or load is say 400W then it does not matter whether you are using a 500W psu or 850W psu. both will consume the same amount of electricity from your mains (provided they are equally efficient or have the same efficiency). the 850W psu will NOT consume significantly more electricity then the 500W psu of equal efficiency. hence the effect in ur electricity bill be negligible.
Another point to be noted is that generally a higher wattage psu has better rated components then their lower wattage siblings.
i have seen many posts here where members ask for the optimum wattage requirement for their system. This Tip is for them.
First roughly calculate the power requirements of ur system depending upon the components and their usage, i.e. whether extreme gaming or not (most power requirement), the concurrent usage of all the components and their duration of use etc...
there are many sites which have the values for your components, just google for it.
after you get a rough figure in watts for ur requirements then multiply that with root of 2 for nominal usage (not extreme gaming)
for example if your requirements comes to 300W (normal power consumption, not peak requirements)
then you should get a psu with real or true 300 x 1.41= 425W approx. output.
if you have high demand like games , heavy cpu intensive tasks, then multiply that figure of 300W by 2 i.e. 300 x 2 = 600W for peace of mind.
it is always a good thing to keep ample head room in reserve as the peak loads can shoot upto 2 times, momentarily, under certain circumstances. Also as ur m/c requires more power it puts the psu under great stress, this leads to increase in temps inside the psu as well as leads to dip in voltages due to the heavy load.
This generally leads to degradation of the "quality" of the power outputs. if you have ample head room then the psu will not be under so great a stress and the efficiency as well as the quality of the power outputs will be maintained.
Bad outputs can kill ur million dollar graphic card in a very short time.
Also remember that by design an smps provides power just as much as the load placed on it. in other words if your running requirement or load is say 400W then it does not matter whether you are using a 500W psu or 850W psu. both will consume the same amount of electricity from your mains (provided they are equally efficient or have the same efficiency). the 850W psu will NOT consume significantly more electricity then the 500W psu of equal efficiency. hence the effect in ur electricity bill be negligible.
Another point to be noted is that generally a higher wattage psu has better rated components then their lower wattage siblings.
obama said:
1 small thing i would like to mention here would be the fact that efficiencies do not follow a linear/flat curve.
Most supplies perform at peak efficiency at around 75-80% load. So your above statement is'nt exactly correct.
Even if i have a couple of 85% efficient rated psus, one a 600 watter and the other a 300 watter, the efficiency at a load of 250watts on both WILL be different even though optimal effeciency is same.
sTALKEr said:
You are 100% correct.
it is the reason i had written "will NOT consume significantly more electricity" and i had kept in mind nominal usage with short bursts of gaming activity.
basically my point was to remove the misconceptions regarding smps psus, in as simple and plain terms as possible. you really think many members here will understand linearity of curves (non female anatomy variety i.e.
)thetechmind
Forerunner
Ok guys sorry to feedin here , but TOO many talks going on PSU's here.....saw it right now in other thread a PSU being discussed even in a download rig section.......now over there the talk was of efficiency and wat not......out there it was suggested that a low powered psu be used for better efficiency ......so does it mean lower the power consumption , lower 'w' needed on the psu = higher the efficiency.....
we normally see 1 thread a week on this and things never settle up......confused peeps would once and for all settle up the agony and will go and buy the vx450 and say "yesss, this is wats needed" , for n00bs like me on this PSU business , i dont understand these misterious calculations , this into this and minus this and add this ......sorry but this is frustrating for a person like me who wants to know abt the truth of psus but is lost in so many threads every week with no resolutions and no conclusions and no stern or unified answer / opinion about it all !
we normally see 1 thread a week on this and things never settle up......confused peeps would once and for all settle up the agony and will go and buy the vx450 and say "yesss, this is wats needed" , for n00bs like me on this PSU business , i dont understand these misterious calculations , this into this and minus this and add this ......sorry but this is frustrating for a person like me who wants to know abt the truth of psus but is lost in so many threads every week with no resolutions and no conclusions and no stern or unified answer / opinion about it all !
stellarhopper
Contributor
sTALKEr said:
agreed abt nonlinearity of efficiency curves, but id like to add..obama said:You are 100% correct.
it is the reason i had written "will NOT consume significantly more electricity" and i had kept in mind nominal usage with short bursts of gaming activity.
basically my point was to remove the misconceptions regarding smps psus, in as simple and plain terms as possible. you really think many members here will understand linearity of curves (non female anatomy variety i.e.
atleast newer/better/costlier supplies have multiple peaks in the efficiency curve.
my corsair tx650 is rated for >80% efficiency at 80%, 50% and 33% loads
sTALKEr said:
This is true, but the real picture isn't as gloomy as you put it. While efficiency is indeed 'optimal' around that ~80% load, the drop/variation in efficiency is usually very very little even at loads down to 20%. We're talking variations as little as 2~5%.
Even the 80 plus rating strictly demands that certified products have "more than 80% energy efficiency at 20%, 50% and 100% of rated load". So as long as you stay above 25%, you should get good efficiency with most PSUs
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