Bestec ATX-300-12Z REV.EHR

[Smellydeli]

Re: Bestec ATX-300-12Z REV.EHR

I don't think the Antec 300 is meant to be Solos replacement. The P18x line IMO is the Solos successor.

The 300 is supposed to be a gamers/enthusiast case on a budget with extra room for more fans without silence in mind.

The Solo is more towards the average consumer who cares more about silence rather than cooling capability.

[370forlife]

Re: Bestec ATX-300-12Z REV.EHR

The 8mm and LTEC I see are either the same chocolate brown as UCC or dark blue.
The 10mm LTEC I see are the same chocolate brown as UCC.
The 8mm/10mm CapXons are also that same chocolate brown.
All 3 brands are using the same color brown.
-
Isn't that SPECIAL!
.

So, delta has always used Ltec and Capxon. Why is something that delta has always done automatically antec's fault? I have about 3 or 4 delta's that all have capxon, taicon, and ltec in them.

[PCBONEZ]

Re: Bestec ATX-300-12Z REV.EHR

Boy, you dunno how OEM contracts work do ya!
Delta builds to order.
How many of those Deltas that you have with those cheap caps are OEM units where the contracting company said 'Built it as freakin' cheap as you can'.

The aggravation with Antec is that -YET AGAIN- they went decent to get good reviews on the review sites and build consumer confidence and then switched to cheap crap [without a price reduction] as soon as they figure no one is looking anymore.
.

[everell]

Re: Bestec ATX-300-12Z REV.EHR

@POM_MJ -
Check for a cap around 2200uF near the 5vsb transformer. It will be on the other side of the 2nd heat sink in about the same position as the green output coil. That's a common failure also.

Toast

I have seen this problem also. On the ATX-250-12Z and ATX-300-12Z, this capacitor is sitting next to a large diode. If the computer is left plugged in and 110vac power applied, this diode is constantly conducting and is a heat generator - a good explanation as to why the capacitor is getting cooked. Bestec has a proclivity to place aluminum electrolytic capacitors next to heat generators! Rather than just replacing the capaacitor, I would recommend installing it such that you can bend the capacitor away from this diode to avoid the cooking effect.

The suspect capacitor is C36. Capacitors C36 and C37 along with a coil form a PI filter for the 5vsb. I have seen several of the C36 fail, but never a C37 fail. There has to be an explanation as to why C36 fails but C37 does not. My only theory is capacitor C36 is being cooked by the large diode next to it. Remember - when the computer is OFF, the 5vsb is still ON. That means the diode is generating heat but the fan is OFF and not providing any cooling effect to take away that heat.

On the ATX-300 12E the same capacitor C36 is next to a power resistor - also a heat source. Had one of them bulging. Replaced the capacitor with extra lead length so that I could bend it away from the heat generating resistor.

Due to catastrophic failures - I won't even talk about the ATX-250 12E!

[Toasty]

Re: Bestec ATX-300-12Z REV.EHR

The EarthWatts EA-500 reviewed by HardwareSecrets.com is not the same as the EA-500D Delta unit. Big differences.

http://www.hardwaresecrets.com/article/526/2

Photos of mine attached.

EDIT - 2nd photo shows a few of the caps that PC was talking about.

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

I've replaced both output caps for 12V rails with 2,200/16V SANYO WX-series,
loaded with the same test system, 12V still supply 11.80V.
picture before replaced.

@POM_MJ -
Check for a cap around 2200uF near the 5vsb transformer. It will be on the other side of the 2nd heat sink in about the same position as the green output coil. That's a common failure also.

Toast

I have seen this problem also. On the ATX-250-12Z and ATX-300-12Z, this capacitor is sitting next to a large diode. If the computer is left plugged in and 110vac power applied, this diode is constantly conducting and is a heat generator - a good explanation as to why the capacitor is getting cooked. Bestec has a proclivity to place aluminum electrolytic capacitors next to heat generators! Rather than just replacing the capaacitor, I would recommend installing it such that you can bend the capacitor away from this diode to avoid the cooking effect.

The suspect capacitor is C36. Capacitors C36 and C37 along with a coil form a PI filter for the 5vsb. I have seen several of the C36 fail, but never a C37 fail. There has to be an explanation as to why C36 fails but C37 does not. My only theory is capacitor C36 is being cooked by the large diode next to it. Remember - when the computer is OFF, the 5vsb is still ON. That means the diode is generating heat but the fan is OFF and not providing any cooling effect to take away that heat.

On the ATX-300 12E the same capacitor C36 is next to a power resistor - also a heat source. Had one of them bulging. Replaced the capacitor with extra lead length so that I could bend it away from the heat generating resistor.

Due to catastrophic failures - I won't even talk about the ATX-250 12E!

C36 this one?
Ok, I will replace it, and also C50 100/50V look like bulged.


after that, I will post the result later.

[everell]

Re: Bestec ATX-300-12Z REV.EHR

Yes - that is the correct capacitor (C36) that we are talking about. If the leads on the diode to the left of the capacitor are long enough, bend it away from the capacitor slightly. That diode is a heat generator.

Capacitor C50 is the filter for the DC voltage going to the pwm chip UC3842. If you see any bulge - replace it.

I checked the 12 volt rail on a Bestec ATX-300 12Z that I have. Using one hard drive and one CD ROM as a load, it measured 11.96 volts until the hard drive stabilized, then slowly drifted up to 12.16 volts and stabilized. I have not replaced the output capacitors on the 12 volt rail, so old capacitors may be giving the loading problem. Either way, it is still in spec.

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

Yes - that is the correct capacitor (C36) that we are talking about. If the leads on the diode to the left of the capacitor are long enough, bend it away from the capacitor slightly. That diode is a heat generator.

Capacitor C50 is the filter for the DC voltage going to the pwm chip UC3842. If you see any bulge - replace it.

I checked the 12 volt rail on a Bestec ATX-300 12Z that I have. Using one hard drive and one CD ROM as a load, it measured 11.96 volts until the hard drive stabilized, then slowly drifted up to 12.16 volts and stabilized. I have not replaced the output capacitors on the 12 volt rail, so old capacitors may be giving the loading problem. Either way, it is still in spec.

Thankyou for reference voltage, I've always see like that on 12V rails of any PSU.
11.80V on 12V rails with small load should be abnormal I think.

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

All the ones that I see in that picture with the X top are OST. I only see one jamicon, and one tk.

I don't know the age or "hours-in-use" of this supply. You may want to investigate those output caps. OST's are known crap and could be weak allowing the 12v to sag.

Toast

Sorry, I was wrong. I've recheck again and found the X top caps are OST like 370forlife said exactly and C36 is OST's 2,200/16V also.
The others on 3.3V rails and 5V rails are OST's 2,200/10V.
Now, I have no caps rated 10V left and 100/50V too, I will goto buy on Saturday.
After recaps, I will post the test results later.
Thankyou everyone for your advise.

[PCBONEZ]

Re: Bestec ATX-300-12Z REV.EHR

If you are sure they are on the 3.3v and 5v rails then 6.3v caps would be fine there.

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

I've got some caps to replace the OST's caps.
They're Rubycon, Sanyo and Panasonic? (not sure)









My DMM is not right here, I will measure voltages and post the result tomorrow.

[Toasty]

Re: Bestec ATX-300-12Z REV.EHR

Nice!

Yes, that's a Panasonic in the last pic. The "M" in the box/circle.

How's the 12v?

Toast

[370forlife]

Re: Bestec ATX-300-12Z REV.EHR

Wait a tick, what are those green X topped ones you put in?

Last I remembered, sanyo's vent is a K.

And that vent on that panasonic is the same as hermei/jamicon!

[Toasty]

Re: Bestec ATX-300-12Z REV.EHR

Yup. DAMMIT! Fakes.

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

Fakes Caps? Oh No!, Are you sure?
It very hard to find those brand in Thailand, I've spend my time to get fake caps?.

[Wizard]

Re: Bestec ATX-300-12Z REV.EHR

I wondered too. Sorry to hear that, Should had gotten samxons from Pope, he's much closer to you globally.

Cheers, Wizard

[Toasty]

Re: Bestec ATX-300-12Z REV.EHR

Panasonic = Capital "T" with ends of top curved up
Sanyo = Capital "K" with the "leg" intersecting the "arm" about 1/3 of the way out. Look closely and also note that the 2 intersections have smooth and rounded corners.
Nichicon = A "+" mark. Many others use this. Likely THE most common marking.
Rubycon = Capital "K" mark where both arms/legs meet at the center of the vertical line. Very fine and clean lines.
United Chemi-con = A "Y" that has equal spacing between each leg and is centered . Think of a pie cut into 3 equal slices. - Note: others use this mark, notably Fuhjyyu


See these threads for some good pics of vent marks:

https://www.badcaps.net/forum/showth...?t=4193&page=2

https://www.badcaps.net/forum/showthread.php?t=2701

Sorry but it seems like you might have been ripped! If the dealer is reputable, I would question him. If he's fair, he'll give you your money back.

Toast

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

Could be possiply, my Sanyo caps are not fake?
from https://www.badcaps.net/forum/showthread.php?t=2701
I've see "X" vent mark for 16V rated, and "K" vent mark for 6.3V rated.

[Toasty]

Re: Bestec ATX-300-12Z REV.EHR

Also, the covering color looks too dark for Sanyo. Your color more closely matches the fakes in Post #22 in that thread from larrymoencurly.

I think the only real ones are the used Rubycons.

Toast

[POM_MJ]

Re: Bestec ATX-300-12Z REV.EHR

I've ordered Panasonic FC and FM seires, but may take one week to arrived.
Now, I've got more Rubycon caps 2200/6.3V and 1500/16V.
I'll change all fake caps and measure voltages very soon.
Thankyou all.