FSP FSP300-60THA(1) will not start...

[cubecompmtdx]

I got this power supply out of a parts system that didn't work. The PSU was the reason the computer wouldn't start. With the unit out of the system, I get 5vsb power but shorting the green and black leads on the 24-pin connector does nothing. The unit uses a mix of Teapo, Jamicon, and OST capacitors, none of which are bulging. The unit uses a DM311 chip for 5vsb, no two-transistor design in this one! This would be a decent power supply if it worked. It originally came in a Acer Veriton system. The original motherboard from the computer worked just fine. Really clean inside too!

[mockingbird]

Re: FSP FSP300-60THA(1) will not start...

Where do you see the DM311? I've found them in 350PN, but I could not find one in the 300THN.

My suggestion would be to do a total re-cap.

[c_hegge]

Re: FSP FSP300-60THA(1) will not start...

The DM311 is located between the 5vsb transformer and primary heat sink, like on all FSPs with DM311 5vsb circuits

[mockingbird]

Re: FSP FSP300-60THA(1) will not start...

Yes, I've found it on other models. I have two models here though, 300THN-B204, and Z350-08ATA, they don't have the DM311. Only chip I can see in that vicinity is the optoisolator.

[retiredcaps]

Re: FSP FSP300-60THA(1) will not start...

I get 5vsb power but shorting the green and black leads on the 24-pin connector does nothing.

I have this exact same power supply that I got as part of a non working system.

Same problem, I have 5V standby, but no other voltages when jumpering green to black. On mine, it had an obvious bad cap. The cap at C13 is a Capxon 3300uF 16V was clearly bloated. I changed it out, but still no go. I'm not too motivated to change out the rest of the caps right now. I would rather troubleshoot by measuring voltages than doing a blind recap.

I also find troubleshooting ATXpower supplies difficult because getting my multimeter probes in certain areas is impossible given the tight fit, the vertical daughtercards and lack of documentation on some of those custom chips.

The original owner took out the DRAM, hard drive, but left in an Intel Quad Q6600. So thanks to the power supply failing, I got a Quad core system so I can't complain.

PS. I think you are the same guy that does

http://www.youtube.com/user/CubeComputerChannel

If yes, great job on your channel. I watch your videos. I learned quite a bit from your channel.

[cubecompmtdx]

Re: FSP FSP300-60THA(1) will not start...

Yes, I run CubeComputerChannel, and I'm glad to hear that you've learned some things from my videos! For those curious about the DM311 chip, I have a picture of it posted in my attachments on this thread.

[retiredcaps]

Re: FSP FSP300-60THA(1) will not start...

With the unit out of the system, I get 5vsb power but shorting the green and black leads on the 24-pin connector does nothing.

I fixed mine. See

https://www.badcaps.net/forum/showthread.php?p=262730

for details.

PM/email sent to you as well in case you are not subscribed to your thread.

[JayArr_BC]

Re: FSP FSP300-60THA(1) will not start...

We repaired one of these today, the fan had stopped and a few output caps had bulged but replacing those didn't help so my tech re-capped the entire supply, still no joy. Then I started wandering around the board with my ohm meter and found one of the main transistors E13009 was leaky. Not shorted enough to blow a fuse or anything just leaky enough that it wouldn't run. I asked my tech if he checked them and he said he had with his (digital) meter and not seen anything funny. My old Simpson 260 analogue meter found the problem yet again.

Lesson of the day: don't overlook your main power semis just because your fuse wasn't blown.

Sub-lesson: An analogue meter can be much better at seeing leaky semis than a digital one.

JayArr

[Heihachi_73]

Re: FSP FSP300-60THA(1) will not start...

I'd replace the caps anyway - it's 8 years old and has the same mix of questionable brands as my old (and parted out) FSP200-60ATV.

The three OST caps (two RLG 4.7uF and an RGP 10uF) I pulled from my FSP were all between 3 and 5Ω despite looking fine on the outside, and at least four Teapo caps were bulged (SEK 220uF, 1000uF and 2200uF, and one SC 3300uF).

[Pentium4]

Re: FSP FSP300-60THA(1) will not start...

OST are strange. I have seen twice now in Powerman PSU's with 100% OST where the fan failed and about half of the little caps dried out and failed, and only a few of the filtering caps failed... (Only 50% of the failed ones bulging)

I agree though, every cap in any FSP PSU should be replaced

[Heihachi_73]

Re: FSP FSP300-60THA(1) will not start...

Not strange, just crap.

[Pentium4]

Re: FSP FSP300-60THA(1) will not start...

Fair enough I replace them on sight, even the small ones. Although I do leave them on the voltage doubler (After testing them first)

[PCBlues]

Re: FSP FSP300-60THA(1) will not start...

I have an old ACER which stopped working. Suspected the PS and tried the usual things.
Applying heat kicked the thing back into action and has done so several times.

[stj]

Re: FSP FSP300-60THA(1) will not start...

then replace the small capacitors.