Date: Wed, 12 Nov 2003 13:46:07 -0800 From: John Niven <[EMAIL PROTECTED]>
On Tuesday, November 11, 2003, at 07:46 PM, Greg Shafritz wrote:Here's what I'm thinking could be the problem:
1. A bad VRAM chip on the video card 2. A defect in the special adapter cable that this card uses (13w3 to DB-15 adapter)
Sounds like a bad VRAM chip. The problem is to tell which one.
If you have a scope you might find it that way (looking at the VRAM output pins for one with no activity).
Put your finger on each in turn - see if one is running hot. Also look carefully at the plastic package of each. Excessive heat can lead to a discoloring as the plastic starts to breakdown.
You might also try "freezer spray", an aerosol can which you spay onto each chip in turn. This cools the chip and may make it temporarily come back to life.
Depending on what type of memory chips were used there may be another possibility. Look up the datasheet for the memory chips used which will give you a pinout diagram of the chips. I can help find the datasheet if you post the markings on the chips, though my best source went paid subscription recently, so they're harder to find than they were.
Identify the power pin on the memory chips. Now, unless the memory chips are 'J' lead, it should be possible (with careful soldering) to lift the power pin of the memory chips one at a time. This will completely disable that chip and by observing the affects you may be able to determine which is the faulty chip.
Jeff Walther
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