Delux ATX-450W extreme upgrade
I helped a friend of mine build a nice new computer a couple months ago. It's got an AMD A10-7850K, 8GB DDR3 1866, a nice Gigabyte mainboard which i can't remember much about other than i recommended it to him and it's got plenty of overclocking options, and a 1TB HDD. Basically a good all-round computer.
He decided to keep his old PSU for a while because "it was only used for a few months in the old system". One of those "Delux" PSUs with the green label. Mediocre at best, motherboard killers at worst... The fan was already sounding bad even though there was hardly any dust in it. We even did some overclocking and it held up, but i wasn't putting my hopes up.
I lent him my old hard drive for a while until he bought the 1TB drive. When he bought that, i suggested that it might not be a good idea to leave that much data at the mercy of that pile of turd, since he intends on working on that computer (Autocad, 3ds max and Photoshop). When he showed me some of the units he was looking at, i proposed that instead of him spending $20-$25 on another PSU that will still be a piece of crap, he'd be better off paying me that to upgrade his current PSU to better parts. And here we go.
The PSU looked like this: No input filtering other than two little Y caps, 470uF main filter caps, 13007 main switchers, EI-33 transformer. The secondary was absolutely pathetic. 20A schottky diodes for 5v and 3.3v, and a *gasp* 12A fast recovery on 12v. Capacitors were all Asia'x, 1000u + 470u on each rail, and only 3.3v had a (sad looking) pi coil, others were simply jumpered. Also interesting to note is that this PSU does not have a 3.3v sense wire. The circuit for it is still there, they just couldn't be bothered drawing one more wire. To compensate for that, the 3.3v rail sits a bit high at 3.42v with no load.
5v and 3.3v each got a 30A schottky, and 12v got 2x 20A schottky in parallel. I had to hack the PCB a little to fit the second 12v rectifier, but nothing major. I also found a larger heatsink of the same shape for the secondary and used that to install the new secondary parts.
All pi coils were installed and the output filter toroid for 5v and 12v was replaced with something more appropriate. Interesting to note is that i checked the two toroids with my LC meter and they registered the same values. Of course, the larger one will have more current carrying capacity before it saturates. The coil i installed used to have a -5v winding as well - i have unwound that before installing it.
The primary side was left alone, other than the addition of an input filter coil. I only have a few 13009s left and i would rather keep them for more profitable projects. Capacitors were basically a grab bag, it was what i had around. A mix of Panny FL, Sanyo WG and an odd "Seacon". I had to drill some extra holes to get them all to fit.
5vsb got two 1500uF 6.3v Sanyo WG. 3.3v got one 3300uF 6.3v Sanyo WG and two 820uF 6.3v Panasonic FL after the pi coil, 5v got one 3300uF 6.3v Sanyo WG and that Seacon 2200uF 10v (had that cap lying around since forever, can't remember what it came out of), and 12v got 2x 1000uF 16v Panasonic FL and another 1000uF 16v Panasonic FL after the pi coil, and one of the Asia'x 1000uF 16v caps originally on the 12v rail got moved on the -12v rail.
All those motherboard-grade caps in there did make the PSU whine under certain loads, so i had to do a couple slight changes to the feedback circuit. YMMV.
To finish, two more SATA+molex chains were added and the fan was replaced with a Yate Loon 2800rpm one. I also installed a temperature control circuit so it doesn't spin full blast if it doesn't have to. The ugly black thing with two blue wires coming out of it in the last pic is a thermistor wrapped in a lot of heatshrink.
And that's how i turned a pile of turd into something that is actually recognizable as a PSU. It may be even 80-plus worthy.
He decided to keep his old PSU for a while because "it was only used for a few months in the old system". One of those "Delux" PSUs with the green label. Mediocre at best, motherboard killers at worst... The fan was already sounding bad even though there was hardly any dust in it. We even did some overclocking and it held up, but i wasn't putting my hopes up.
I lent him my old hard drive for a while until he bought the 1TB drive. When he bought that, i suggested that it might not be a good idea to leave that much data at the mercy of that pile of turd, since he intends on working on that computer (Autocad, 3ds max and Photoshop). When he showed me some of the units he was looking at, i proposed that instead of him spending $20-$25 on another PSU that will still be a piece of crap, he'd be better off paying me that to upgrade his current PSU to better parts. And here we go.
The PSU looked like this: No input filtering other than two little Y caps, 470uF main filter caps, 13007 main switchers, EI-33 transformer. The secondary was absolutely pathetic. 20A schottky diodes for 5v and 3.3v, and a *gasp* 12A fast recovery on 12v. Capacitors were all Asia'x, 1000u + 470u on each rail, and only 3.3v had a (sad looking) pi coil, others were simply jumpered. Also interesting to note is that this PSU does not have a 3.3v sense wire. The circuit for it is still there, they just couldn't be bothered drawing one more wire. To compensate for that, the 3.3v rail sits a bit high at 3.42v with no load.
5v and 3.3v each got a 30A schottky, and 12v got 2x 20A schottky in parallel. I had to hack the PCB a little to fit the second 12v rectifier, but nothing major. I also found a larger heatsink of the same shape for the secondary and used that to install the new secondary parts.
All pi coils were installed and the output filter toroid for 5v and 12v was replaced with something more appropriate. Interesting to note is that i checked the two toroids with my LC meter and they registered the same values. Of course, the larger one will have more current carrying capacity before it saturates. The coil i installed used to have a -5v winding as well - i have unwound that before installing it.
The primary side was left alone, other than the addition of an input filter coil. I only have a few 13009s left and i would rather keep them for more profitable projects. Capacitors were basically a grab bag, it was what i had around. A mix of Panny FL, Sanyo WG and an odd "Seacon". I had to drill some extra holes to get them all to fit.
5vsb got two 1500uF 6.3v Sanyo WG. 3.3v got one 3300uF 6.3v Sanyo WG and two 820uF 6.3v Panasonic FL after the pi coil, 5v got one 3300uF 6.3v Sanyo WG and that Seacon 2200uF 10v (had that cap lying around since forever, can't remember what it came out of), and 12v got 2x 1000uF 16v Panasonic FL and another 1000uF 16v Panasonic FL after the pi coil, and one of the Asia'x 1000uF 16v caps originally on the 12v rail got moved on the -12v rail.
All those motherboard-grade caps in there did make the PSU whine under certain loads, so i had to do a couple slight changes to the feedback circuit. YMMV.
To finish, two more SATA+molex chains were added and the fan was replaced with a Yate Loon 2800rpm one. I also installed a temperature control circuit so it doesn't spin full blast if it doesn't have to. The ugly black thing with two blue wires coming out of it in the last pic is a thermistor wrapped in a lot of heatshrink.
And that's how i turned a pile of turd into something that is actually recognizable as a PSU.
It may be even 80-plus worthy.
Attached Files
was the -5V winding the only difference between the two?
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