Delta electronic atx 600W - 5V drop

[emilije]

Hi to all,

I have Delta electronics ATX power supply 600W (dps-600mb)

It won't start with load (for example with halogen lamp 20W) on 5V line. If i connect only one hard drive and start ps by shorting pin 14 with ground, it will start OK. However, if i put two HDD's, fan is working and other voltages are present (12V, -5V, 3.3V) but 5V drops to 4.1V and HDD's are not spinning. If i connect third hdd, ps will shut down.

Main problem was that computer didn't start after being turned off until main plug was unplugged from wall socket, and 5-10mins pause.
Computer is now working with new PS, but i wanna repair this and use it as a spare for testing.
Two caps in red circle were bulged and replaced with new ones (Yageo low esr 105C)
any ideas?

[emilije]

Re: Delta electronic atx 600W - 5V drop

Update: While loaded with two hard drives, 5V has 0.38V ripple showing almost full ac wave. On 12V ripple is much smaller, like 0,09V. I have portable scope and can post pics if needed.

these are esr in circuit readings:
3330uF 6.3V and 10V 0.01ohm
2200uF 6.3V 0.03ohm
2200uF 10V 0.01ohm
1000uF 16V 0.02ohm

any hints, pls?

[Th3_uN1Qu3]

Re: Delta electronic atx 600W - 5V drop

Your replacement caps are either bad or not soldered properly.

[emilije]

Re: Delta electronic atx 600W - 5V drop

You mean on those two in red circle? Because i only replaced those two, i didn't replaced others on right board.
btw those two were replaced with Yageo low esr 105C