Help removing large cpu soldered to pcb

[mbgillespi]

Hello all! This is my second post here. Thanks to the information on the forum boards, I've had a fair amount of success with both gold and silver.

I am having a problem, however. I have a large cpu soldered directly to the pcb that I want to remove before processing (pics below). I've cooked it in HCl in a low-heat crock pot for about 4 hours, but to no avail. The ceramic capacitors scraped off easily, but the cpu won't budge. Am I just not waiting long enough? Do I need to add peroxide? Any suggestions would be most welcome.

Cheers!
Matthew

 

[joubjonn]

That's an AR job. Once you get the MLCC's off, AR is the process to use. I wouldn't do it with just 1, 10 CPUs like this should give a couple grams. The pins are going to be magnetic anyway, so it would be the same process for the pins as the plated top piece. I just did two batches of ceramic cpu's in AR and was very happy with the results.

 

[etack]

I would use heat.
Use a heat gun and melt the solder.

AR is not good for this step. your gold could get caught in the layers of the PCB.

Eric

 

[Anonymous]

MAP gas torch on the rear of the board. Wait till the solder melts and prise the chip off with a screwdriver.

Not pretty, but do it outside!

 

[philddreamer]

Heat is the way to go. Even a propane torch will do.
I took 6 of these off the other day, among other material.

Phil

 

[alexxx]

I took 6 of these off the other day, among other material.

Phil

beautifull cpus, with style... never saw one of these before...

 

[philddreamer]

never saw one of these before...

Neither have I, Alex. I've been wanting to ask the fellow members if any have seen them, and if they are worth saving.

 

[Geo]

I found some just like that in some imaging processors. The ones I had was made by Cisco though but look the same in the same configuration. I think they are for graphics acceleration.

 

[necromancer]

i have a old portable BBQ, heat the back & smack the front of the board off the ground, works foe me.

here is my version of those chips

 

[glorycloud]

A heat gun will heat up the solder holding that Samsung Alpha CPU to the PCB board.
When the solder gets hot (maybe after a minute or so) you can use a flat head screw
driver in between the CPU and the board to remove to separate the CPU from the board.

This is much easier to do with the CPU still on the board. Just turn the board upside down
and heat the area where the pins from the CPU are showing underneath the board and
the CPU will most times just drop off the board due to the weight of the CPU pulling downward
from the force of gravity.

These are beautiful chips. It is sad to see them go bye bye into an acid bath.