Toshiba Satellite l455d-s5976 GPU reflow

[Faizi Ahmed]

a couple of months ago my toshiba satellite l455d stopped working , when i switch on the power only the power light comes on and nothing comes on display , usually after hitting the power switch power led then the wifi led switched on then bios is showed on display , well i took it to a repair guy and he charged me with 20$ and gave it back to me after a week saying the graphics card (ATI Radeon) was not working , well it worked for a month then stopped working again , same issue , i took it to another guy he said the same thing about graphics card and repaired it in front of me , he just heated the gpu chip for a couple of minutes and it started working , it worked for 2 more months and now the same thing happened , it took it apart and heated the gpu with a heat gun for a while (1 or 2 minutes) saw the flux melting then let it cool down for a while then assembled it back , but its not working , am I doing the reflow wrong ? should i let the heatgun on the chip a little longer ??

 

[Faizi Ahmed]

the heat gun looks like this
http://img.waffleimages.com/0f3a11279163db1b20b62c9c4e3fee001d9c8588/aoyue850a.jpg
no temp mentioned but heat levels from 1-8 , i put it on at 3 for a minute twice , saw the flux(the golden crystalline thingy) melt and then let it cool

 

[Rob57]

You heated the flux and not the solder. If you look at specific instructions on Youtube, the solder must be heated to between 183 to 210 degree Fahrenheit to flow. You need to protect the other electronic parts located around the GPU with aluminum foil; shiny side up. (One place actually cuts a square from an unfolded pop can with a Dremel tool and places it as a surround for the GPU to avoid the other parts being heated up.) You definitely need to heat it up a bit hotter. There are two places on line that do they work and guaranty it for 1 year. They add additional 5 mil thick thick piece of copper leaf over the the GPU and affix it with heat sink compound. This seems to help prevent a recurrence.