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.
Now the kicker - I recently found a NuBus extender card :-) This would make debug much easier. I'm willing to loan it out for the cost of shipping, if you are serious about this debug.
John
-- Vintage Macs is sponsored by <http://lowendmac.com/> and...
Small Dog Electronics http://www.smalldog.com | Enter To Win A | -- Canon PowerShot Digital Cameras start at $299 | Free iBook! |
Support Low End Mac <http://lowendmac.com/lists/support.html>
Vintage Macs list info: <http://lowendmac.com/lists/vintagemacs.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/vintage.macs%40mail.maclaunch.com/>
Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
