Bestec ATX-300-12Z Cap list

[ratdude747]

Does anybody have a junk/spare Bestec of the title's model that they could get the cap values off of?

My aunt's desktop has one with some junky fried OSTs and jamicons and half of them I can't get the values off of. She's out of town and her grandson needs to use it a bit; I can't take the PSU home and desolder it.

Either that, or if you happen to have a good quality ATX 20+4 300W+ unit you want to sell for cheap (bad caps OK since I can fix that at home), PM me.

[Pentium4]

Re: Bestec ATX-300-12Z Cap list

I've practically remembered all of them. As far as I'm aware it might depend a little bit on the revision. There are only two that are hard to find lytic-wise (It uses three 0.1uF 63V lytics) I've replaced them with ceramic caps but haven't measured ripple with a scope. It seemed to function fine.

For 12V: 1000uF 16V x2 (I use 1500uF or 2200uF)
For 5V: 2200uF 10V x2
For 3.3V: 2200uF 10V x2
For 5VSB: 2200uF 10V x2
For -12V: 1000uF 16V (I usually use 680uF)
The rest of the caps consist of:
22uF 50V
10uF 50V
1uF 50V x3
100uF 35V (Sometimes 220uF 35V)
47uF 50V

Just in case it varies, just have a few on hand of 1uF, 2.2uF, 10uF, and 22uF 50V

I leave the CapXon on the voltage doubler because 680uF is plenty for a 300W PSU and They usually test within 5% spec after years of use.

[c_hegge]

Re: Bestec ATX-300-12Z Cap list

Another difference I've seen an a few 300-12Zs is the use of a 1000uF and a 2200uF cap on the 12V output.

[Pentium4]

Re: Bestec ATX-300-12Z Cap list

True, some of the newer ones have 2200uF. Either capacitance is a suitable replacement because it's almost always general purpose 105C caps that Bestec uses

[c_hegge]

Re: Bestec ATX-300-12Z Cap list

Yup. I usually use Panny FC for most of them, and FK for the 2200uF 16V cap.

[kc8adu]

Re: Bestec ATX-300-12Z Cap list

as a test i used 1200@16 zl in all output cap positions.
seeing that some came with 1000@10 everywhere but +12.
passed all tests better than atx spec.so entry level low esr caps like fc will be fine.
as noted here before some come with gp caps!

[ratdude747]

Re: Bestec ATX-300-12Z Cap list

It's from a 2005-2006 vintage compaq... I should have gotten the revision. Damn it.

[Pentium4]

Re: Bestec ATX-300-12Z Cap list

as a test i used 1200@16 zl in all output cap positions.
seeing that some came with 1000@10 everywhere but +12.
passed all tests better than atx spec.so entry level low esr caps like fc will be fine.
as noted here before some come with gp caps!

It accepted that low of ESR? That's really good to know. I have tons of ZLH and ZLJ that would be perfect for these 12Z's. Normally I use KY and PW

[mockingbird]

Re: Bestec ATX-300-12Z Cap list

Bestec ATX-300-12Z, Revision "CDR":



1) 16V 2200uF 10x26mm Jamicon "TK"
2) 16V 1000uF 10x21mm Jamicon "TK"
3) 10V 2200uF 10x21mm Jamicon "TK"
4) 10V 2200uF 10x21mm Jamicon "TK"
5) 16V 1000uF 10x20mm Jamicon "TK"
6) 10V 2200uF 10x21mm Jamicon "TK"
7) 10V 2200uF 10x21mm Jamicon "TK"
8) 10V 2200uF 10x21mm Jamicon "TK"
9) 50V 220uF 5x11mm Jamicon "TK"
10) 63V 0.1uF 5x11mm Jamicon "TK"
11) 50V 1uF 5x11mm Jamicon "TK"
12) 50V 0.47uF 5x11mm Jamicon "TK"
13) 50V 2.2uF 5x11mm Jamicon "TK"
14) 50V 10uF 5x11mm Jamicon "TK"
15) 63V 0.1uF 5x11mm Jamicon "TK"
16) 16V 2200uF 10x25mm OST "RLS"
17) 50V 10uF 5x11mm Jamicon "TK"
18) 50V 100uF 8x11.5mm Jamicon "TK"
19) 50V 10uF 5x11mm Jamicon "TK"
20) 63V 0.1uF 5x11mm Jamicon "TK"
21) 50V 2.2uF 5x11mm Jamicon "TK"

Have fun removing all the carbonized glue.

[momaka]

Re: Bestec ATX-300-12Z Cap list

It accepted that low of ESR? That's really good to know. I have tons of ZLH and ZLJ that would be perfect for these 12Z's. Normally I use KY and PW

I repaired one with Nichicon HN and HZ. Ran stable afterwards. I don't have a scope so can't tell you exactly how clean the power was, but it was a freebie repair as were the caps (came from a used Xbox 360)... so yeah.

Bestec PSUs aren't particularly picky about caps. Same with HiPro of that era - they'll just take nearly anything. IIRC, c_hegge even tried polymers in a 250W HiPro, and not only it worked, but output ripple was quite low too. Most other PSUs usually aren't like that and may oscillate. Sirtec, for instance, are insanely picky.

[Wester547]

Re: Bestec ATX-300-12Z Cap list

IIRC, c_hegge even tried polymers in a 250W HiPro, and not only it worked, but output ripple was quite low too. Most other PSUs usually aren't like that and may oscillate. Sirtec, for instance, are insanely picky.

It was a 300W Hipro:

http://hardwareinsights.com/wp/poly-...tually-work/9/

And the ripple voltage and voltage regulation didn't change much at all when he used polymers in place of Teapo SCs. So Hipro's feedback loop is designed very well. In fact, the whole output filtering circuit is very overspec'd, especially in those older Dell, HP, and Compaq 250W-300W units. They would often have larger toroids than those found in most 300-350W units and very thick heatsinks...

Not to say Bestec is bad, with a recap their power supplies seem solid to me, especially since they don't use conductive glue anymore (at least not as much as they used to). The ATX-300-12Z is a decent unit for sure, very overbuilt in terms of secondary rectifiers.