Good Linkworld PSU

[Pentium4]

Linkworld was decent.....back in the day. This thing looks like it could easily do 350W! That little board on the AC receptacle has 4 Y caps (safety approved), 2 X caps (0.47uF), a coil, and the fuse. Once it gets to the board, there's an NTC thermistor, 2 more Y caps, another 0.47uF X cap, a 2nd coil, and 2 MOV's. Nice! The bridge rectifier is rated for 8A, 680uF Canicon bulk caps, TO-247 13009 switchers on the primary.

The main transformer looks to be ERL39 which is pretty surprising for a 350W PSU, let alone a Linkworld one The 3.3V uses SBL4045PT, two 2200uF 10V caps, and a coil. The 12V uses an MBR20100CT, one 2200uF 16V cap (12.5mm slot) and the largest PI coil. 5V uses SBL4045PT, two 2200uF 10V caps, and a coil. Even the -12V and -5V use a 470uF 16V cap and a coil. The caps consist of Canicon, CS, and Fuhjyyu. The only caps that are bulging are Fuhjyyu.

It looks like Linkworld used their own custom supervisory chip? That's pretty neat. Uses a Yate Loon fan for the exhaust and the Globe Fan for the intake. Here's what I don't understand....why is the ground wire of the Globe fan soldered to the 5V?! Only the rear fan is connected with that thermistor, the Globe Fan seems to run at full speed. Soldering is pretty bad but can be redone... The toroid coils look on the small side but at least they have a lot of wire on the cores. Sadly, this thing is seriously lacking in the cable department. It only has a 20 pin, 4 pin P4, 4 molex, 1 floppy. Not much room at all to add more cables.

[goodpsusearch]

Re: Good Linkworld PSU

12-5V=7V

The Globe fan is actually connected to 7V with this trick. Interesting.

That Linkworld supervisor chip is a collector's item!

Overall, an impressive power supply from a well known at that time psu manufacturer! Thanks for sharing!

[Pentium4]

Re: Good Linkworld PSU

12-5V=7V

The Globe fan is actually connected to 7V with this trick. Interesting.

Interesting. I didn't know it worked that way, thanks for clarifying that.

That Linkworld supervisor chip is a collector's item!

It's the first one I've seen, I thought it was pretty cool too

[momaka]

Re: Good Linkworld PSU

Wow, very nice unit, indeed. And look - they used a proper glue to hold down the components! None of that conductive tan crap nonsense.

It's funny that the Fuhjyyu were the only caps to blow. I thought Fuhjyyu was better than that. I guess it's more of a "run of the batch" with them now, since some seem to last forever unless harshly overheated, while others die easily. All the ones I have are the former case.

I'm guessing 2-transistor 5VSB. But that's not too bad. Also, the "dancing PI coils" for the -5V and -12V rails look kind of funny. Other than that, it looks like a very decent PSU overall. 39-size transformer - nice! I wonder what is used for the switchers.

Interesting. I didn't know it worked that way, thanks for clarifying that.

Yup, there are many ways to permanenty wire a fan without necessarily forcing it with 12V.
You also have the options of 8.7V (12V - 3.3V), 17V (12V - (-5V), or 12 + 5), and 24V (12V - (-12V)). Okay, that last one is a bit ridiculous. I remember trying a 80 mm 0.3A Delta fan on around 20V, and it sounded scary. No, really, I tested that on a bench PSU at my previous university during one of our labs, and people were turning around to see what the noise was .

[cheapie]

Re: Good Linkworld PSU

You also have the options of 8.7V (12V - 3.3V), 17V (12V - (-5V), or 12 + 5), and 24V (12V - (-12V)). Okay, that last one is a bit ridiculous. I remember trying a 80 mm 0.3A Delta fan on around 20V, and it sounded scary. No, really, I tested that on a bench PSU at my previous university during one of our labs, and people were turning around to see what the noise was .

I tried 24V with a 80mm Nidec Beta SL fan once. It started spinning very fast, then shut off until it got to a more normal speed, then sped back up, and so on. Almost as if it has overspeed protection.

I would try it with my Delta AFB1212GHE (120 mm, 240 CFM, 62 dBa, 3 amps), but I don't want to break it, as it's a very expensive fan, and I don't want it flying apart or whatever, as that could be very dangerous. My power supply also doesn't have a powerful enough -12V rail (it's only 0.8A).

[Pentium4]

Re: Good Linkworld PSU

Wow, very nice unit, indeed. And look - they used a proper glue to hold down the components! None of that conductive tan crap nonsense.

Yes! Sometimes I will entirely chuck a nice PSU because I don't feel like removing all the conductive glue...

It's funny that the Fuhjyyu were the only caps to blow. I thought Fuhjyyu was better than that. I guess it's more of a "run of the batch" with them now, since some seem to last forever unless harshly overheated, while others die easily. All the ones I have are the former case.

Yeah, I guess I need to pull them all and test all their ESR. Maybe the other caps are failing as well.

I'm guessing 2-transistor 5VSB. But that's not too bad. Also, the "dancing PI coils" for the -5V and -12V rails look kind of funny. Other than that, it looks like a very decent PSU overall. 39-size transformer - nice! I wonder what is used for the switchers.

Yeah, 2 transistor. Seems about right for 2004. Yeah it's funny that they raised the coils so much off the board. It uses Fairchild 13009's.

Yup, there are many ways to permanenty wire a fan without necessarily forcing it with 12V.

That's really cool. I'm surprised though that the sleeve bearing fan is still so loud @ 7V

[momaka]

Re: Good Linkworld PSU

Past 6V, their speed tends to increase exponentially and all the way up to 12V.

[RJARRRPCGP]

Re: Good Linkworld PSU

2004

In 2004, AMD still made Athlon XPs (Probably the best year for Athlon XPs) and even then, Asus motherboards for them still ran off the +5 V rail. IIRC, you will never find an Asus socket 462 motherboard off the +12 V rail!

[Pentium4]

Re: Good Linkworld PSU

Past 6V, their speed tends to increase exponentially and all the way up to 12V.

I thought it was just because the bearing was dry but it didn't really improve after cleaning and relubing. What I have noticed is that some sleeve bearing fans make weird sounds when running at a certain angle. They seem to run the most silent when running with the sticker facing up

[momaka]

Re: Good Linkworld PSU

What I have noticed is that some sleeve bearing fans make weird sounds when running at a certain angle. They seem to run the most silent when running with the sticker facing up

Yes, I've noticed that too. I think it's because when running with the sticker up, the fan rotor assembly (the blades) are suspended just by the magnetic field of the permanent magnet and the shaft and sleeve bearing barely have to do anything... whereas in other positions, there is always some friction between the sleeve bearing and the shaft. In the up position (sticker facing down), there is usually a plastic or teflon washer/ring at the rotor end of the shaft that comes in contact with the sleeve, thus rubbing with it and slowing the fan a little.

[Pentium4]

Re: Good Linkworld PSU

I might replace the sleeve bearing globe fan. I have yet to recap it. I really dislike the lack of cables

[goodpsusearch]

Re: Good Linkworld PSU

You can add cables from dead psus.