hi,
quick story recap -
pc failed to switch on again after poweroff, was intermittant then every time failed. Full power off and on would get it POSTing ok.
Replaced all obviously failed caps on output filter side and then almost always posted first time but sometimes not.
Decided to recap entire thing (further 12 caps including primary side, with best Panasonic ones I could get FM, TSED series etc.) and after connected to my pc (which nicely blew my USB controller after powering on) I thought I best test it some more before making same mistake again....
Situation: PSU loose, connect AC cord only, these are voltage readings, the 5v standby is ok but voltage is getting to 3.3, 15 and 12v rails somehow? (Voltages measured with negative lead on pin3)
pin | V | my readings
1 | 3.3V | 1.67
2 | 3.3V | 1.67
3 | COM |
4 | 5V | 2.31
5 | COM |
6 | 5V | 2.31
7 | COM |
8 | PWR_OK | 33mV
9 | 5VSB | 5.05
10 | 12V | 5.59
11 | 3.3V | 1.67
12 | -12V | -5.3
13 | COM |
14 | PS_ON | 5.05
15 | COM |
16 | COM |
17 | COM |
18 | -5V | -3.4
19 | 5V | 2.31
20 | 5V | 2.31
Everything seems ok, I cannot for the life of me see anything wrong but something obviously is, has anyone encountered this or electronically minded suggest what may be wrong?
(The only other thing I removed was the 3 FETs? on the primary side that were on the heatsink to be able to get to some of the small caps, but seem to be all back on ok.) 2 were identical and large, one was smaller. The 2 larger ones had same writing on and may have gone back reversed, but assume as same item that is irrelevant.
If anyone could help that would be great!
cheers
quick story recap -
pc failed to switch on again after poweroff, was intermittant then every time failed. Full power off and on would get it POSTing ok.
Replaced all obviously failed caps on output filter side and then almost always posted first time but sometimes not.
Decided to recap entire thing (further 12 caps including primary side, with best Panasonic ones I could get FM, TSED series etc.) and after connected to my pc (which nicely blew my USB controller after powering on) I thought I best test it some more before making same mistake again....
Situation: PSU loose, connect AC cord only, these are voltage readings, the 5v standby is ok but voltage is getting to 3.3, 15 and 12v rails somehow? (Voltages measured with negative lead on pin3)
pin | V | my readings
1 | 3.3V | 1.67
2 | 3.3V | 1.67
3 | COM |
4 | 5V | 2.31
5 | COM |
6 | 5V | 2.31
7 | COM |
8 | PWR_OK | 33mV
9 | 5VSB | 5.05
10 | 12V | 5.59
11 | 3.3V | 1.67
12 | -12V | -5.3
13 | COM |
14 | PS_ON | 5.05
15 | COM |
16 | COM |
17 | COM |
18 | -5V | -3.4
19 | 5V | 2.31
20 | 5V | 2.31
Everything seems ok, I cannot for the life of me see anything wrong but something obviously is, has anyone encountered this or electronically minded suggest what may be wrong?
(The only other thing I removed was the 3 FETs? on the primary side that were on the heatsink to be able to get to some of the small caps, but seem to be all back on ok.) 2 were identical and large, one was smaller. The 2 larger ones had same writing on and may have gone back reversed, but assume as same item that is irrelevant.
If anyone could help that would be great!
cheers
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