Friday, April 22, 2011

Compaq C500 - Bad Video Memory

Compaq C500 Arrives with bad video. 


The information is displayed just not properly. External LCD also displays same thing. This is related to the video memory of the unit and not the GPU in this case. 


This will require a low temp reflow. Because video memory is often not glued to the mother board, low heat has to be used so that the chips become separated from the motherboard. If that happens it will require special equipment and higher cost to the customer.


If you unit does not have dedicated memory for video, then it would be the chip that addresses (provides the row and column information for the GPU) the video memory.   This is usually a large chip directly to the side or near the GPU. Typically on Intel models rather than AMD. 


Middle picture shown after reflow.




 Link Video showing screen issue at Youtube 
if you have issues displaying from blog.

2 comments:

  1. Great Tutorial. I was wondering what you mean though by a 'Low Temp Re-flow as I thought that in order to do a re-flow the temp would need to reach 217 degrees before the un-leaded solder would melt?

    Krist

    ReplyDelete
  2. A low temp reflow - a term that I use for smaller parts such as video ram, though the temp is the same, I use the low 'wind' setting on my heat gun. If the chips are heated too hot like with the GPU reflow, the close proximity and smaller solder balls will pool together shorting the video memory. When I set for low temp, I use a liquid water based flux.

    This reflow will not take as much heat/time as the GPU because they are ceramic, and video memory is encased in plastic.

    Perhaps it was a confusing term, but the whole chips do not get as hot as with the GPU as in nVidia relows.

    I hope that does make things clearer.

    ReplyDelete

I cannot repair laptops for you via the internet, I can only answer questions related to posts. This is because I have not had experience on every motherboard that is out there. Bear with me.

If you do need it repaired. Contact me for quote (US/CDN Only)

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