[rescue] the cause of the dead cpus ?

[Curtis H. Wilbar Jr.]

There are components on the back of the board <sigh>....

-- Curt

>Date: Thu, 15 May 2003 11:54:20 -0400
>Subject: Re: [rescue] the cause of the dead cpus ?
>From: Dave McGuire <mcguire at neurotica.com>
>To: The Rescue List <rescue at sunhelp.org>
>Content-Transfer-Encoding: 7bit
>
>On Thursday, May 15, 2003, at 11:12 AM, Curtis H. Wilbar Jr. wrote:
>> If anyone was following the thread where I mention I ended up with a 
>> lot
>> of 10 "as is" (read "Dead") Slot 1 CPUs... I'm not sure but I have a 
>> theory...
>>
>> Many of them now seem to (not for any extended duration) test ok now...
>> the only difference is I'm using one of those metal clips to hold on 
>> the
>> heatsink rather than those cheap plastic "pin type" retainers.  I think
>> it is putting pressure on the CPU differently (and possibly stronger) 
>> by
>> the heatsink and back casing.
>>
>> What I'm wondering is if the solder connections of the actual CPU (a
>> BGA chip) to the slot 1 PCB is defective.  So, when I use the stronger
>> clip to hold on the heatsink it is helping to compensate for bad
>> solder connections of the BGA chip to the board....
>>
>> Does this sound realistic ?  Don't suppose anyone out there has the
>> equipment necessary to reflow BGA soldered chips ? :-)
>>
>> I wonder how I can verify this theory ?
>
>   Yes, this is certainly possible.  I have a reflow hotplate, but that 
>will only be useful if there are no components on the back of the board 
>and everything "meltable" (clips, etc) can be removed.  We can give it 
>a shot if you want.
>
>          -Dave
>
>--
>Dave McGuire                "They live deeply, these vagabonds."
>St. Petersburg, FL                            -Goro
>_______________________________________________
>rescue list - http://www.sunhelp.org/mailman/listinfo/rescue