Archived from groups: comp.sys.ibm.pc.hardware.systems,comp.sys.ibm.pc.hardware.misc,alt.comp.hardware.homebuilt (
More info?)
Arno Wagner wrote:
> In comp.sys.ibm.pc.hardware.misc David Maynard <dNOTmayn@ev1.net> wrote:
>
>>Arno Wagner wrote:
>
>
>>>In comp.sys.ibm.pc.hardware.misc David Maynard <dNOTmayn@ev1.net> wrote:
>>>
>>>
>>>>Ian Harding wrote:
>>>>
>>>>
>>>>>Arno Wagner wrote:
>>>>>
>>>>>
>>>>>
>>>>>>In comp.sys.ibm.pc.hardware.misc Falcon1209 <falcon1209@hotmail.com>
>>>>>>wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>>Hi,
>>>>>>
>>>>>>
>>>>>>
>>>>>>>I recently assembled a P4 3.0 GHZ computer and it has been making
>>>>>>>excessive amounts of noise. I replaced the faulty video card fan with
>>>>>>>a new 3rd party fan and it still makes the noise. It makes less noise
>>>>>>>the first few minutes of startup and remains relatively quiet until I
>>>>>>>start using resource demanding applications such as games, WinRAR, or
>>>>>>>QuickPAR. Its a really loud humming noise almost a buzzing noise.
>>>>>>>Possibly coming from CPU or Power Supply
>>>>>>
>>>>>>
>>>>>>
>>>>>>>Any suggestions?
>>>>>>
>>>>>>
>>>>>>
>>>>>>Overloaded cheap PSU without overload protection? A PSU should not
>>>>>>make these noises except when close to or over the allowed load.
>>>>>>
>>>>>>Arno
>>>>>
>>>>>
>>>>>Not necessarily overloaded, although cheap may be a factor! I had a
>>>>>similar problem with a brand new Q-TEC 400W PSU recently, swapped back
>>>>>to the 350W obscure brand PSU that came with a ?35 case and it was fine.
>>>>>
>>>>>Ian
>>>
>>>
>>>>Numbers I found on a review of the Q-TEC 400W Dual Fan Gold
>>>
>>>
>>>>Total "Real" power output [W] 300 (Peak 400)
>>>>Output current +5V [A] 25A (Sticker 30A)
>>>>Output current +12V [A] 12A (Sticker 16A)
>>>>Output current -5V [A] 0,5A (Sticker 1,0A)
>>>>Output current -12V [A] 0,5A (Sticker 1,0A)
>>>>Output current +3.3V [A] 14A (Sticker 20A)
>>>>Output current +5V STB [A] 1,5A (Sticker 2,0A)
>>>>Maximal total power for 3.3 and 5 combined [Watt] 150 W (Sticker 180W)
>>>
>>>
>>>>That '400 watt' is 'peak' power but it's really a 300 Watt supply (assuming
>>>>you can believe their 'confessional' numbers).
>>>
>>>
>>>Yes, this is a perfectly correct labeled 300W (400W peak) PSU.
>
>
>>Where did you get the ideal it's 'labeled' a 300 Watt supply? It's labeled
>>and sold as a "Q-TEC 400W Dual Fan Gold."
>
>
> From this line here:
>
> ">>Total "Real" power output [W] 300 (Peak 400)"
>
> You mean this part was not on the label? If so, you are perfectly
> correct that it is mislabeled and sold as a far more powerful unit
> than it actually is.
Right. The numbers up there were what the person posting the review (on a
reseller's site in the "user reviews" section) said was in the email he
received from Q-Tec when he queried about the specs and the apparent reason
for the email is he was having all sorts of power up problems with it
(which doesn't help the 'spin up' theory any).
>>>What do you not like about this?
>
>
>>Putting on the sticker that +5V is 30 Amps when it's capability is 25 Amps,
>>or that 3.3V is 20A instead of 14A, or that 12V is 16A instead of 12A is
>>not "perfectly correct labeled."
>
>
>>I'm going by what a purchaser said he got from Q-Tec when he emailed them
>>because I can't, for the life of me, find a single amp rating on their
>>entire web site.
>
>
> O.K., that is a definite "hands off" indication. If they hide their
> specs then there is something fishy.
>
>
>>http://www.qtec.info/products/product.htm?artnr=13023&specs=1
>
>
>>>Since HDD spin-up generates much
>>>higher load, doing this type of design is appropriate in
>>>PC PSU design. Or did they claim 400W _sustained_ on the
>>>box?
>
>
>>'Peak' without a time interval means nothing. Tell me it's 400 watts for 30
>>seconds and maybe I'll buy that's for spin up time but just "400 watts
>>peak," if they had bothered to even mention 'peak', could be for 5
>>nanoseconds for all anyone knows. Btw, what is it that's supposedly being
>>'spun up' on the 3.3V rail so that it's labeled 20 Amp when it's really 14?
>
>
> "Peak" rating for PSUs is in the 1...30 Minute range in sensible
> designs.
Would seem to make over current protection problematic if you're going to
allow '30 minutes' of non sustainable operation.
> If they do not say anything, then that is a bad sign.
Yeah. Not publishing specs is always a bad sign. However, even if the
'peak' were a valid surge rating I'd still have problems with calling the
PSU that. A "300 Watt PSU (peak 400)," perhaps; but not "400 Watt Dual Fan
Gold." And not even if they said "400 Watt (peak) PSU" because that says
nothing about what the 'real' (sustainable) watts are (not to mention you
need amps per rail anyway and they don't publish that at all).
>
> O.K., I misunderstoos what was actually on the label and
> what you got from other sources. I agree with you now that
> I know the details.
Understandable.
I should repeat that I haven't seen the sticker either. As I said, I'm
going by the 'user review' but, after seeing the Q-Tec site with no
meaningful specs at all, I tend to believe him.
I should also note that even if all the, IMO deceptive, numbers were
'explained' on the label that that's 'too late'. You had to BUY it,
thinking it was a 400 Watt PSU, to 'discover' you got a 300 Watt PSU.
> Arno
>