Biostar A770E3 and Antec Truepower Trio recap

[whitelabrat]

Hi Folks!

So my 5yr old computer started to get funny. Too many charred parts on the motherboard so it went to the trash. I quickly discovered that for the same price as used 939 socket motherboard I could just replace the motherboard, RAM, and CPU with more up to date parts. A Biostar A770E3 for $30 is hard to beat, but you get what you pay for. I had to RMA the first board and I should have the new board today.

Since I had some downtime with the home computer, I figured I do a visual inspection of my Antec Truepower Trio 550 which probably has between 10,000 and 20,000 of hrs on it at least plugged in and providing maintenance current. Much to my displeasure it is packed with OST capacitors just like the Biostar A770E3. Only the big 400v cap is United Chemicon which looks OK, but I may replace it with a nice Panasonic.

I already placed an order with Mouser to replace the electrolytics on the A770E3 with either organic polymer Nichicons, or electrolytic Panasonic FM's. Good stuff. So I'll have to make an extra order for the Antec parts. Either way it should be much cheaper than a new power supply, and probably more reliable too.

Anyway. I'm hoping to post some photos and share my experiences with this little project.

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

I haven't looked at a Trio but you may run into 3300uf-4700uF 10mm caps that you can't get at Mouser.

Badcaps.net carries some Samxon RS series that are about the only available option for those particular caps.
.

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

@PCBONEZ: Thanks for the tip.

I got a good close look at the Trio last night. One thing I like about this PS is that there is some wiggle room in the layout. It's a real hodge-podge collection of values in there though. I'll post a list later.

Obligatory disclaimer: Most switching power supplies have one large high voltage capacitor. BE SURE THAT CAP IS DRAINED BEFORE WORKING!!! A high voltage shock can be lethal!!! For example the Trio has a gigantic 400v 390uF cap that would seriously hurt/kill you. Use something like a 10K resistor on a stick to short the capacitor, and verify with a voltmeter. Be safe. You've been warned.

Some crummy photos attached.

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

Hmmm. Can anyone ID those solid capacitors in the closeup of the motherboard? I'm tempted to replace the v16's with 2200uF Panasonic FM's. My guess is those are 270uF's. They ought to have a good ESR, but without looking at a datasheet it's anyone's guess. The FM's have long life and very good ESR and the added bonus of capacity.

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

4x 270uF does seem a little light.
Better brands of boards tend to use 4x330uF or 3x470uF for the 16v. [Over 1320uF total.]

It is possible that Lytic over near the USB in last pic is in parallel with them.
Mixing Lytics and Polys in +12v in the VRM isn't that unusual.

.

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

Those caps are these.


Despite being poly their ESR is not impressive.
uF should he higher with that high of ESR.
.

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

@PCBONEZ: Wow thanks!

Compared to a Panasonic EEU-FM1C332L, I'd say that's pretty unfortunate. The Panny's are likely more reliable too. So those will get swapped out. I'll leave the ones on the other side of the filters alone.

Offtopic: Many folks seem to think the block filters are better than the toroidal filters that we're used to seeing. I'd venture to guess that a toroid with a cheap core is still better than the ones on my board. I should have yanked the toriods off my old board and swapped them in here.

I realized how much I can't stand leadless solder. I had to crank up the heat on the iron to get the solder to melt. I find that putting in a bit of leaded solder helps me work at lower temperatures. I'm worried so much heat on the leads will damage the capacitors.

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

You know those FM are 12.5mm right?
.
They should work if they'll fit in there.

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

Yup. 12.5mm seems to fit ok for 3300uF but the 2200uF... well, I got it in, but not pretty. I'm not going to post any photos cause it's just embarrassing. In any case I'm typing this on the computer now and it seems stable so far.

For the Antec Trio I used a Panasonic TS-ED for the 400v cap. Better than the United Chemi-con SMQ it replaced. Again, not a perfect fit, but some artistic rearrangement of the heat sink fins and it was no problem. The rest of the caps were either Panasonic FM or FR's with one exception. I forgot to order one 10v 2200uF, so I used a 35v 2200uF United Chemi-con. It's one of their low ESR caps, but I don't recall what. So this Antec Trio should perform better and last forever.

As for the A770E3 I replaced most of the large uF caps with Panasonic FM's. I apparently suffer from BOM amnesia, because I forgot 10v 1000uF caps and I didn't order enough 6.3v 1000uF caps. I had one 10v 1000uF FM. I used a Nichicon PW 3300uF 10v that I had laying around too. I left the OST's near the USB ports alone. I ended up using Nichicon solid 470uF caps to replace the four 1000uF caps near the memory slots. They were all in parallel so I figure 1880uF of low ESR would do fine.

I didn't bother with the 4x 270uF near the CPU. I do have 16v 3300uF Panasonic FM's for that job, but I was getting frustrated with the solder on the board. It was a bear working with that lead-free stuff. Likewise left most of the 16v 100uF caps alone for now. If things get funny, or some rainy day, then I'll swap 'em out.

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

Update. So the board was a little more stable after my last post, but apparently not enough. The CPU power supply just didn't have enough performance to deal with the strong mains line noise I was getting. I noticed that whenever my Isobar power strip started buzzing (dirty mains power) the computer would blue screen or do other nasty things. It was obvious that the CPU was unstable.

To confirm my suspicion I dropped in an isolation transformer. Buzzing on the power strip, no crashing. So I've replaced the wimpy CPU power supply caps with the big 3300uF Panasonic FM's. It's been a week and rock solid so far.

I should note that I RMA'd the first board. Looking at this board it's obvious that the CPU power supply caps had been replaced. Note to Biostar: you can't fix a bad component by replacing it with the same junk.

Photo attached. Hope this has been helpful to folks.

[Toasty]

Re: Biostar A770E3 and Antec Truepower Trio recap

<snip>
Offtopic: Many folks seem to think the block filters are better than the toroidal filters that we're used to seeing. I'd venture to guess that a toroid with a cheap core is still better than the ones on my board. I should have yanked the toriods off my old board and swapped them in here.<snip>

The "block" filters are in fact toroids, just horizontal and encased to allow machine insertion. Tear one apart and you'll see.

Toast

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

@ Toasty

That's not necessarily true. Without taking the chokes apart we'll never really know for certain. It would be quite a small toroid if that were true. In any case, if I were manufacturing a super cheap motherboard like this one, I'd expect a simpler inductor such as a wire wrapped around a ferrite core instead of the familiar doughnut shaped toroid which generally cost more to manufacture.

For Example...

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

Not Toroids but not simply coils either. - Ferrites.
The difference is only style.

Your buddy over at Hardware Secrets is a nice guy but he's not the sharpest knife in the drawer.
The Vcore caps are all in a single parallel bank after the OP of the phases becomes a common line.
As such showing the Vcore caps as components of any particular phase as shown in that drawing is not correct.
.

[Per Hansson]

Re: Biostar A770E3 and Antec Truepower Trio recap

PCBONEZ; True but then again it is how mainboard manufacturers describe their boards
"It's got 24 phases, so it is 2458 times better than that other model!!!1ONE"

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

Yeah. The link was just for the photo. I liked how the wire was exposed in the photo. I have no comments about the publisher.

It does seem that the chokes have some sort of shielding material around them. Mine appear to either be painted or coated in plastic, which would have me conclude they have a metal shielding. All just wild speculation on my part. The A770E3 has a lousy 3+1 CPU power supply.

Interesting note, I was able to unlock an extra core on the Sempron 140 and it's been stable for a night while doing some heavy lifting. It's never been stable when unlocked otherwise.

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

PCBONEZ; True but then again it is how mainboard manufacturers describe their boards
"It's got 24 phases, so it is 2458 times better than that other model!!!1ONE"

That's not what I was saying.
He has the topology [as he likes to say] wrong in the drawing.
The Vcore caps are not part of the phases as he depicts.
.

[PCBONEZ]

Re: Biostar A770E3 and Antec Truepower Trio recap

It does seem that the chokes have some sort of shielding material around them. Mine appear to either be painted or coated in plastic, which would have me conclude they have a metal shielding. All just wild speculation on my part. The A770E3 has a lousy 3+1 CPU power supply.

The wire is coated because it's wrapped on an iron slug.
Same iron core material as used in Toroids.
If it wasn't coated it would short.
-
The surround is just a potting fixture.
The coating there is also for insulation.
.

[whitelabrat]

Re: Biostar A770E3 and Antec Truepower Trio recap

A bit delayed, but I want to point out that this mobo is actually pretty good, but it doesn't like 1.5v RAM. It can't do less than 1.6v which is why I was having stability problems. After putting in some compatible RAM it has been rock solid with the new caps. Zero crashes ever. Super clean power matters.

[larrymoencurly]

Re: Biostar A770E3 and Antec Truepower Trio recap

A bit delayed, but I want to point out that this mobo is actually pretty good, but it doesn't like 1.5v RAM. It can't do less than 1.6v which is why I was having stability problems. After putting in some compatible RAM it has been rock solid with the new caps. Zero crashes ever. Super clean power matters.

That's the first time I've heard of memory needing a lower voltage instead of a higher one to work right. What kind of memory is it?