Cheap power supplies - false advertising?

Redmint

Redmint

Redmint

Soldato
Joined
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Okay it's generally agreed that the cheapo £30 for 700W (or whatever) power supplies usually won't be able to supply their rated power, however I wondered the other day if this is actually false advertising/illegal? Forgetting for a moment that you'd have issues drawing the rated power with the pathetic number of connections they supply you with, surely if someone could prove that these units can't actually do what they claim then the companies selling this **** should get in trouble for it?

If a food company claimed they were selling you 35g of crisps but all the bags were only actually 25g I'm sure they'd get in trouble? I can't see how the law should be any different for manufacturers of computer parts.
 
Perhaps there is some minor loophole, i.e. it delivers 700w in a specific (not real world usage) benchmark.

Either way, indeed, it sucks :¬)
 
I think the companies can get away with it if the power supply can reach that figure, even if only briefly (few seconds) without dying. Sure it's something along those lines.
 
Just like fan makers, wireless speed, wireless range, battery life manufacturers/advertisers boost their figures by using theoretical figures. Cheap PSUs rend to be rated by adding up each rail and calculating the wattage from that. Of course there's no way they could ever simultaneously provide that power but in theory it could for a few seconds. It's not illegal but people still get sucked into the lie.
 
As people above have said, it's not technically false advertising, as there are different ways of calculating the total wattage a PSU is able to supply. And (however briefly) the PSU will probably be able to output its rated power, before bursting into flames and taking the rest of your PC with it.

Most cheapo PSU manufacturers stay away from listing the PSU's efficiency on the box or listing it in the specs sheet as it will be disastrously low. A good PSU can get +80% efficiency, but a cheapo PSU will be in the low 50% or even 40% efficiency, costing you on your electricity bill, and probably reducing the life of the PSU dramatically.
:)
 
Also, a lot of the ratings are at low temperatures (like 30 degrees or less) even though at full load, with the included fans/heatsinks, a standard case and a normal room tempeature the PSU will get much hotter than this temperature. Perhaps they do one test while inside a cold room?
 
Surely being able to supply the stated wattage for a few secs in a cold room is still misleading though? If a power supply claims 700W then surely it should be able to supply this consistently under "normal" circumstances? I mean if your CPU/RAM could only run at it's rated speed in a cold room for a few secs you'd complain?

Tealc said:
Of course there's no way they could ever simultaneously provide that power but in theory it could for a few seconds.
Click to expand...

"In theory"? Would like to see any review/test where they actually manage to draw the rated power even for a few secs before it explodes...
 
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usually they can supply very high current on the 3.3 and 5v rails and then have low power 12v rails (where your need the power for GPU's) and then add the 400w 3.3volt line 100w 5v line and 200w 12v line, bobs your uncle you have 700w :D
 
Redmint said:
Surely being able to supply the stated wattage for a few secs in a cold room is still misleading though? If a power supply claims 700W then surely it should be able to supply this consistently under "normal" circumstances? I mean if your CPU/RAM could only run at it's rated speed in a cold room for a few secs you'd complain?
Click to expand...

i completely agree, the power advertised should be what is achieveable under normal household use, not super-chilled sub second silly number! :eek:
 
same as all walks of life im afraid, Speaker performance is the same with some companies saying there system has 1000w of Power but its not its all calculated, Same as monitors and TV's they all work around the true figure and add things together to make lovely marketing numbers. thing is for the majority of the public it works and sells how ever there is a minority (us lot for example) who actually want to use the power or have nicer things and we know what to look out for. but yes it is a Con but if you see a 700W psu for £30 you know something is not right
 
No but the cheap amp connected to it could set fire to your house, i work for a electronics certification company and its amazing the amount of poor / dangerous electronics people fill there houses with. But any way back on track yes its not good and should not be aloud but it happens just checknthe amps on the rails for a true power of the unit
 
Do these power supplies actually blow up at its rated wattage? i just googled but not much info on them as of yet.

Never used them to its limit and only in cheapo server PCs for trust reasons.. but do they actually not work at rated wattage?


also, what kind of failures are we speaking here,
 
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good god. that thing went on sale :eek:

that video has been favourited. should shock anyone i know who wants to get a cheap PSU, and make them change their mind.
 
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