Allied AL-8400BTX - freebie

[Dan81]

Some of you might have known I got a mysterious package comprised of three motherboards and two PSUs. One of the PSUs was this Allied AL-8400BTX, and the other was a very old 230W Sun Pro. (worth nothing,seriously )

As I had some free time in my hands, and after failing at fixing my K7VZA motherboard (I'll start up a thread about this later - maybe some of you can chime in and tell me what to do at this point), I said why not give this PSU a shot. After all, it has a 6 pin PCI-E connector.

So, first inspection revealed the usual stuff - bad caps - one bulging 1000uF 10v (for pete's sake, why 10v? Was 16v not cheaper?), and another two bulgers of the exact same value and diameter on the 5v rail.

Other noticeable stuff was the heatsinks were quite thin, but tall enough. I don't know what's up with Allied on these, as my other AL-8400BTX ( just to clarify a few things - there are two versions - one with a glossy, tiger-like texture surface, and a dull matte gray version. The other one that I'm going to tell about is the matte version.) has thicker heatsinks, but they're shorter. Another thing that is different on these is the grille - the matte grey version has a honeycomb pattern arranged to form a square while the glossy version has the pattern extended on the whole side of the PSU.

One common thing across both revisions? Both versions had ERL-28 transformers, although with rounded edges unlike the usual ERL-28 which has square edges. (example being my 230W Sun Pro.)

The first thing I did was remove the bad caps. Since I wasn't going to do a full recap at the moment (I have to stock up on caps - even if they're GP caps, I had no problems in using Samwha RD 2200uF 16v 105*C caps.) I simply reused some caps from another Deer (a solid low end 250W max Premier rated for "400W".)and also took the bigger transformer (EI-33 - still an slight improvement over ERL-28, don't ya think?) and installed it in there. The caps I used were two 1000uF 16v radioactive green Yang Chun (Saturn) cap and a Panasonic FL 1000uF 16v pull from a MB for the 5vSB.

Plugged it in,fired it up. Voltages came in spec. For some funny reason the thermistor is glued to an Su'scon 1000uF 16v cap. (probably responsible for 12v, as the spot it is in allows for a much bigger cap, about the same diameter as my Samwha RD 2200uF 16v caps.)

Some pictures attached.

Stay tuned, as I got some more stuff in the works this month.

-Delux ATX-450W P4 complete overhaul - 120mm case
-Allied AL-A400ATX complete overhaul
-Linkworld LPK19-30 460W
-Mercury MAV-230 230W/ Sun Pro teardown/ list of parts.
....maybe an complete overhaul of this Allied too?

[momaka]

Re: Allied AL-8400BTX - freebie

Some pictures attached.

Yay! You attached pictures

... I said why not give this PSU a shot. After all, it has a 6 pin PCI-E connector.

So, first inspection revealed the usual stuff - bad caps - one bulging 1000uF 10v (for pete's sake, why 10v? Was 16v not cheaper?), and another two bulgers of the exact same value and diameter on the 5v rail.

Lol, the PSU has a 6-pin PCI-E power connector, but looks like the filtering is quite inadequate - at least judging by the 5V and 5VBS rails.

For a PSU with a 6-pin PCI-E, I would expect at least one 2200 uF and one 1000 uF cap on the 12V rail.

But hey, worst case, you can always cut the 6-pin PCI-E connector away and put it on a more capable PSU.

Other noticeable stuff was the heatsinks were quite thin, but tall enough. I don't know what's up with Allied on these, as my other AL-8400BTX... has thicker heatsinks, but they're shorter.

Oh Deer!

One common thing across both revisions? Both versions had ERL-28 transformers, although with rounded edges unlike the usual ERL-28 which has square edges. (example being my 230W Sun Pro.)

28-size transformer?!? Ugh.
What's a 6-pin PCI-E connector doing on that PSU then? Heck, what's even a 4-pin 12V CPU connector doing there? With a tiny main transformer like that and the typical low-switching frequency for these half-bridge designs, don't expect powering anything more than a Pentium 3 or an AMD Duron reliably. I wouldn't push more than 100-120 Watts continuous. Anything above that will just make the PSU run hot and degrade the caps.

The first thing I did was remove the bad caps. Since I wasn't going to do a full recap at the moment (I have to stock up on caps - even if they're GP caps, I had no problems in using Samwha RD 2200uF 16v 105*C caps.) I simply reused some caps from another Deer (a solid low end 250W max Premier rated for "400W".)and also took the bigger transformer (EI-33 - still an slight improvement over ERL-28, don't ya think?) and installed it in there. The caps I used were two 1000uF 16v radioactive green Yang Chun (Saturn) cap and a Panasonic FL 1000uF 16v pull from a MB for the 5vSB.

Good job.
Yes, the 33 size transformer should help push a few more watts... well, if the primary transistors and their drivers allow it, of course. And then there's the output coil - I've seen quite a few burned ones in cheap PSUs, so that's another weak point to think about.

Stay tuned, as I got some more stuff in the works this month.

-Delux ATX-450W P4 complete overhaul - 120mm case
-Allied AL-A400ATX complete overhaul
-Linkworld LPK19-30 460W
-Mercury MAV-230 230W/ Sun Pro teardown/ list of parts.
....maybe an complete overhaul of this Allied too?

Go for it!

Just give us better pics, if possible. The above ones are pretty badly focused. Even a cheap film camera can take better shots if you have a way to scan them and convert them after that.

[Dan81]

Re: Allied AL-8400BTX - freebie

Lol, the PSU has a 6-pin PCI-E power connector, but looks like the filtering is quite inadequate - at least judging by the 5V and 5VBS rails.

For a PSU with a 6-pin PCI-E, I would expect at least one 2200 uF and one 1000 uF cap on the 12V rail.

But hey, worst case, you can always cut the 6-pin PCI-E connector away and put it on a more capable PSU.

As I said, I'm expecting to recap it with Samwha RDs this month. I had quite good experience with these. Worst case, I have an Modecom that I can stuff inside this Allied case and reuse the wires. That one has very thick heatsinks and a true ERL-35 transformer, not to mention 13009 transistors. This Allied uses usual 13007s it seems. Funny thing, one of my Allied PSUs (the one with the 120mm fan more exactly) used a 13007 as the standby transistor (which usually is a 2N60 MOSFET most of the time) and TT2194 main switchers.

28-size transformer?!? Ugh.
What's a 6-pin PCI-E connector doing on that PSU then? Heck, what's even a 4-pin 12V CPU connector doing there? With a tiny main transformer like that and the typical low-switching frequency for these half-bridge designs, don't expect powering anything more than a Pentium 3 or an AMD Duron reliably. I wouldn't push more than 100-120 Watts continuous. Anything above that will just make the PSU run hot and degrade the caps.

Yeah, for some reason these come with ERL28 transformer. Only my 120mm version of the AL-A400ATX came with a true ERL-35 transformer and well...the Deer built Modecom I have.

Good job.
Yes, the 33 size transformer should help push a few more watts... well, if the primary transistors and their drivers allow it, of course. And then there's the output coil - I've seen quite a few burned ones in cheap PSUs, so that's another weak point to think about.

Not by much, but still better than a 28er. 13007 transistors and the output coil is quite small but thick.

Go for it!

Just give us better pics, if possible. The above ones are pretty badly focused. Even a cheap film camera can take better shots if you have a way to scan them and convert them after that.

I'll definitely look into that.

[PeteS in CA]

Re: Allied AL-8400BTX - freebie

... Funny thing, one of my Allied PSUs ... used a 13007 as the standby transistor (which usually is a 2N60 MOSFET most of the time) ...

Other than the 13007 being beefier than necessary for the 10W or 15W Standby circuit (a 13005 would probably be sufficient), that isn't unusual. What folks here call a "two transistor" Standby inverter-regulator has been around for a very long time. Boschert, in the late 70s and the early 80s used MJE13005s and MJE13007s in their OL25 and a whole bunch of low-medium power XL## discontinuous flyback designs. Unlike the infamous MB-killer "two transistor" Standby circuits, Boschert - and other power supply manufacturers - included an SCR OVP crowbar circuit that protected 5V-powered loads from and over-voltage condition. If the PSUs with MB-killer Standby circuits are worth upgrading, adding an SCR OVP crowbar circuit would be pretty easy.