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The 2013 El-cheapo Power Supply Roundup

PostPosted: December 29th, 2013, 10:21 pm
by c_hegge

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: December 30th, 2013, 8:20 pm
by Wester547
What was the intake temperature when testing the CP-350, if you remember? Was it getting hot at 370W load (if you also remember)? Most older Huntkeys like that explode at the labeled rating, even at 240V. There's another review of the CP-350 which was conducted on a 220V/50Hz line voltage with an intake temperature of 30-31*C and it couldn't even do 350W without fireworks (after a few minutes, no less, and it had worse power factor throughout the testing), yet despite using slightly different secondary rectifiers and a somewhat different bridge rectifier, but in every regard, looks completely comparable to the one you have, including the fan, but it looks like the one in the other review was spinning at full speed the whole time. I wonder how yours did better? Lower intake temperature? The one in the other review also has a different supervisory IC, maybe that's part of it. Long Runner wasn't kidding about the ferrite coil doing nothing with only one capacitor, as far as ripple voltage goes, this is a good testament to that.

Also, it is likely that the ratings on the label are more representative of the limits in the transformer windings (how power is distributed per rail there) than the rectifiers (hence +12V being rated higher than +5V).

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: December 30th, 2013, 9:51 pm
by LongRunner
From the page for the unbranded unit:

Test 1′s ripple results aren’t shown in the table, but it’s obvious from that test that the 5vsb rail doesn’t like not having a load on it, as the ripple on that rail was at 260mV during that test – over five times the maximum limit. Thankfully, this is an unrealistic scenario in a PC. All computers will put a load on the 5vsb rail.

I disagree with that being acceptable. It indicates that the control loop is unstable. Whatever that leads to is anyone's guess. The least they could have done is put a minimum load resistor there.

Still, I know it would be nitpicking, assessment-wise, when it can't even regulate properly.

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: December 31st, 2013, 1:30 am
by c_hegge
I didn't measure the intake temperature, as I didn't have the X-vision fan controller when I tested the Huntkey (I test these units throughout the year). I don't think it was all that high, though.

I am inclined to agree that it is not good design on the ATX2000 with the 5vsb rail. However, I don't usually knock points of in a review over issues which are not going to affect the user.

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: December 31st, 2013, 8:46 pm
by Wester547
If the load tester is really as loud as it sounds in the video (both the new one and old one), how can you tell how loud the power supply fans are with all that "extra" noise? :P

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: December 31st, 2013, 9:20 pm
by LongRunner
By temporarily switching off the load tester's fans...?

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: January 1st, 2014, 1:28 pm
by c_hegge
^
Yes

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: January 3rd, 2014, 2:26 am
by LongRunner
From the NSCom's page, just out of curiosity:

The two primary capacitors are rated at 560µF, but most 560µF capacitors are physically larger than these parts, so it wouldn’t surprise me if they are actually only 470 or even 330µF.

You can, in fact, get high quality 560µF 200V capacitors with the same case size (22mm diameter by 30mm height, if I'm viewing correctly) as those shown, including 105°C versions. Specifically:

Chemi-con SMQ (85°C 2000h) and KMQ (105°C 2000h)
Nichicon GG (105°C 2000h) and LG (85°C 2000h)
Panasonic TS-HC (105°C 2000h)
Rubycon USG (85°C 3000h)

I'm not saying the rating of the caps in question is real, though, just that it could be in theory. Who knows how outdated the manufacturing processes for the crap caps are...

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: January 3rd, 2014, 2:52 am
by c_hegge
Note how I said most, not all. I have seen 560uF caps that size before too, but in these cheap no name caps, it's rare

Re: The 2013 El-cheapo Power Supply Roundup

PostPosted: January 3rd, 2014, 3:26 pm
by Schafskopf
hi,

at first i'd like to say that this is really a nice roundup again. It's always nice to have something to show people who buy cheap power supplies :D

some hints regarding the manufacturers:

The Bliss is probably from XHY power (xin hui yuan). These power supplies are quite common here in germany, because we have at least two companies (Inter-Tech and Xilence) who sell that crap. There is sometimes a marking "XHY" beyond the primary heatsink (like on this picture)

The PSI is indeed a very old Solytech (although at first I didn't believe that, because todays Solytech units look quite different). The fan is an old Globe Fan - they also look quite different today, but one might recognize that the logo is still similar.

And the Zumax is probably made by Topower themselves. That would mean that it is rather old already, because afaik they closed their facilities some time ago.