Author Topic: 300W ATX PSU turns on for a split second then dies (Read 1970 times)

ranronqx · « **on:** November 24, 2008, 04:09:25 PM »

anu po posible nangyari sa psu after nireplace ung bulging caps along 3.3 and 5v rails, nagshu-shutoff na after turning on for 2 to 3seconds. Nung una nagkaganito din to usually first hour in the morning when i turn on the pc pro maaayos rin after ko idetach ang power cord then apply long pressed to power button for 10 to 15 second then plug it back, tuloy-tuloy na power nya, un nga lang namamatay bigla ung pc. Pero knina nde na nadala sa technique ko hehehehe....I've check the primary and secondary regulators with a vom and DMM ok nman, ung lm339 and KA7500B nireplace na (KA7500B replaced with MB3769) . any ideas po mga gurus? intermediate lang po alam ko sa elec troubleshooting.BTW... model ng psu is Pentium IV EZ-300W ATX

sana po may mkapagbigay ng idea. mga sir HELP PO!

Philippine Electronics Forum · « **on:** November 24, 2008, 04:09:25 PM »

boki · « **Reply #1 on:** November 22, 2009, 01:12:55 PM »

Check you CPU heatsink if it is properly attached, if not, the CPU will get overheated that caused your system to shut off

Philippine Electronics Forum · « **Reply #1 on:** November 22, 2009, 01:12:55 PM »

I n s i d e r 2010 · « **Reply #2 on:** November 22, 2009, 01:16:24 PM »

try u sa ibang pc bossing,pag shut down parin sure nasa mother board. pag ok na sure nasa pc parin kaya check u ung mga resistor sa trigger ng input or primary . hope makatulong

Philippine Electronics Forum · « **Reply #2 on:** November 22, 2009, 01:16:24 PM »

bugsky777 · « **Reply #3 on:** December 17, 2009, 05:41:10 PM »

check mo tol yung thermal paste sa heatsink baka tuyo na.. baka overheat yung pro kaya nag shashutdown

Philippine Electronics Forum · « **Reply #3 on:** December 17, 2009, 05:41:10 PM »

ronelex · « **Reply #4 on:** November 30, 2011, 05:58:26 AM »

sa mga inayos ko dito sa ofis. If test the power supply iikot for 3sec0nds ang fan din off ang supply. Kadalasang problema sa psu ay mga output na diode na kamukha ng transistor pero may diode sign ang marking. Kadalasan ang pang 12v ang nasisira.
cause: mahina na ang ikot ng fan dahil sa mga alikabok kung kaya nag.ooverheat at nasisira ang mga pyesa.
sana nakatulong, based on my experience lang po

Philippine Electronics Forum · « **Reply #4 on:** November 30, 2011, 05:58:26 AM »

ars · « **Reply #5 on:** December 02, 2011, 08:34:37 AM »

ts...replace nyu po ung 470uF/16v 2 pcs yata un...sana mkatulong

Tukkar · « **Reply #6 on:** January 06, 2012, 02:09:11 PM »

From my experience too....leaky caps o yung mga lumobo ng electrolytics subukan mo palitan at saka yung ultrafast o diodes stack check mo kung okay pa....one thing more ..cold solders...

pete · « **Reply #7 on:** January 06, 2012, 05:43:22 PM »

Quote from: Tukkar on January 06, 2012, 02:09:11 PM

From my experience too....leaky caps o yung mga lumobo ng electrolytics subukan mo palitan at saka yung ultrafast o diodes stack check mo kung okay pa....one thing more ..cold solders...

binuhay ang bangkay hehehehe

01110011 · « **Reply #8 on:** January 06, 2012, 05:52:55 PM »

itest mo without any load by connecting the green wire to ground.
try mo kung gagana sya kung hindi. its time to buy a new one

??? · « **Reply #9 on:** January 07, 2012, 08:17:49 AM »

Binubuhay talaga. hehehe

your most RIDICULOUS man :) · « **Reply #10 on:** January 07, 2012, 08:49:30 AM »

Quote from: 1SaGing5 on January 06, 2012, 05:52:55 PM

itest mo without any load by connecting the green wire to ground.
try mo kung gagana sya kung hindi. its time to buy a new one

tomoo! pag gumana naman sa board or overhet cpu

stealthwalker · « **Reply #11 on:** May 09, 2012, 09:08:22 PM »

sis/sir try mo muna tanggalin PSu from board them short green & black sa duration pag naka-On yung PC tingin ko kasi bloated caps prin sa PSu problem mo..

Philippine Electronics Forum · « **Reply #11 on:** May 09, 2012, 09:08:22 PM »

Philippine Electronics Forum