BFG 550W Model: BFGR550WGSPSU Rebuild

[LDSisHere]

This is the power supply out of my mother's computer that I built in early 2010. Due to the education I have received from this forum, I have been doing preemptive rebuilds on my power supplies. I have now moved on to looking at my parents computers.

Overall I am very pleased with the build of this supply, if not the capacitors that were used. Surprisingly, it uses a DM0265R for the 5VSB so there is no need to mod this supply. Another thing I noticed was how the PCB was marked 350 to 450 in a supply marked 550.

What I am not sure about is if I should replace the main capacitors. The last picture shows the Teapos that came in the supply and some old Rubycons that I had removed from a supply I junked a while back that I am considering using in place of the Teapos. The ESR on the Teapos is 0.03 Ohms and the Rubys is 0.05 Ohms and I do not have any idea of the Rubys age. I am willing to buy new ones but I would rather not if I can avoid it. I am going to replace all the other caps but I would like some input on what I should do about the main caps, leave them, tape up the old Rubys and use them, or just buy new ones?

Thanks guys,
Lloyd

[999999999]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

Yeah it's really a 450W PSU marketed and labeled as though you can add all the rails together and call it something higher.

The "main caps" are usually good for the life of the PSU, unless the fan(s) fail and they overheat a lot. I'd put the Teapos back in unless you can find a date code on the Rubycons to confirm they aren't more than a few years old, but even then only you can guess what % of that period they were in use. If the junked supply was very clogged with dust or suffered a fan failure I would avoid using them.

If it has a sleeve bearing fan you might want to lube it while you have the PSU open.

[LDSisHere]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

Thanks for your response. My only concern was that they were 85 deg caps. This supply has never been overheated and it does not push too much of a load. The Rubycons that I have are old, I just looked at the date code. I will save them for testing or if I run across some Fuhjyyu caps, I replace that brand on sight. Good idea on the fan I will look at it when I finish the recap of this supply.

[tom66]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

85°C is fine in primary or as general use caps (i.e. decoupling, timing, control loop.)

[goodpsusearch]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

Those Rubycon are real keepers. They are 105°C rated primary caps. I would use them in a power supply with APFC. APFC boosts the voltage to ~400V and stresses the primary caps.

[Behemot]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

Yeah but PSU's with APFC don't usually use two 200V caps in series. I have never seen it on my own eyes, just once here on photos.

Anyway, if you decide to change the Teapos, keep them anyway. May come handy into some slightly crappier PSU with low input capacitance according to it's power output (it is usually good to provide 1 uF per 1 W).

[goodpsusearch]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

Yeah but PSU's with APFC don't usually use two 200V caps in series. I have never seen it on my own eyes, just once here on photos.

Anyway, if you decide to change the Teapos, keep them anyway. May come handy into some slightly crappier PSU with low input capacitance according to it's power output (it is usually good to provide 1 uF per 1 W).

You are right, psus that are designed to have APFC use 400V primary cap(s).

I come across many power supplies, though, that have APFC in the shape of an add-on board (for example Antec Smartpower). Those still have 2x 200V primary caps.


I never trash caps in general.

[mockingbird]

Re: BFG 550W Model: BFGR550WGSPSU Rebuild

BFG = Bankrupt. Farewell guys.