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<blockquote data-quote="Vipersan" data-source="post: 766376" data-attributes="member: 325666">Hi friends ..Perhaps not the best time to tackle such a repair ..but the lapop in question was donated by the owner ...after diagnosing the classic HP overheat problems ...My hands are not working too well atm ..due to a re-visit of the TM I suffer from ..but having ordered a hot air re-work station a few weeks back ...it arrived today CSI825A ..The Compaq 6735S ws already stripped down ..and I'd nothing to lose ..Symptoms ..Powers up ...but Caps lock light continually flashing ...hard drive ..and DVD drive constantly spinning up ...Unable to power off by normal means ..Neccessary to remove battery and or mains to shut it down ..Nothing on the lcd display ...never posts bios ..Cause - bad connections (dry joints) under the GPU (AMD) chip ...due to poor design and bad cooling ..Its a surface mount bga chip ...so no connections accessible ..The guaranteed cure is to remove ...reball ..and refit the chip in question ..But the gear to do this is expensive ..and requires good eyes and steady hands ..neither of which I can claim these days ..Next best cure (possibly only temporary...but proving the cause) ...is to wrap the main board in aluminium foil with only the chip exposed through a hole ..The pre-heat to 100 deg C ..for 3 minutes ...then a 10 minute blast at 200 deg C ....et voila ..Not fully rebuilt the lappy yet ..but it now posts bios ...<img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite8" alt=":D" title="Big Grin&nbsp; &nbsp; :D" loading="lazy" data-shortname=":D" />success ...?? ... well time will tell ..but its a first for me ..rgdsVS</blockquote>

[QUOTE="Vipersan, post: 766376, member: 325666"] Hi friends .. Perhaps not the best time to tackle such a repair ..but the lapop in question was donated by the owner ...after diagnosing the classic HP overheat problems ... My hands are not working too well atm ..due to a re-visit of the TM I suffer from ..but having ordered a hot air re-work station a few weeks back ...it arrived today CSI825A .. The Compaq 6735S ws already stripped down ..and I'd nothing to lose .. Symptoms .. Powers up ...but Caps lock light continually flashing ...hard drive ..and DVD drive constantly spinning up ... Unable to power off by normal means .. Neccessary to remove battery and or mains to shut it down .. Nothing on the lcd display ...never posts bios .. Cause - bad connections (dry joints) under the GPU (AMD) chip ...due to poor design and bad cooling .. Its a surface mount bga chip ...so no connections accessible .. The guaranteed cure is to remove ...reball ..and refit the chip in question .. But the gear to do this is expensive ..and requires good eyes and steady hands ..neither of which I can claim these days .. Next best cure (possibly only temporary...but proving the cause) ...is to wrap the main board in aluminium foil with only the chip exposed through a hole .. The pre-heat to 100 deg C ..for 3 minutes ...then a 10 minute blast at 200 deg C .. ..et voila .. Not fully rebuilt the lappy yet ..but it now posts bios ... :D success ...?? ... well time will tell ..but its a first for me .. rgds VS [/QUOTE]

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