G3 OS10 upgrade Video Probs

[dadofelliott]

System
Purple iMac 200?
Got it free
G3 400mhz
10 gig hd
300+ pc100 ram stock +recent 256K pc100 upgrade

Ram upgrade no prob. OS 10 tiger complete install cd. A bit through told to upgrade firmware to continue then screen goes black without me touching a thing. Reset and hear normal startup sounds with no video.

Take it to compusa and guy tells me crt is toast. I can't see it conking like that so I take it home run it up and let it sit. Black screen but then I hit apple button and screen comes on with shadowing as described by repair tech. I do some screen adjustments and it looks great. I try to reload os 10 and same thing happens again.

I don't think it's a crt prob but now I'm out about $300.00.
I would appreciate any advice.

 

[dtravis7]

It sounds like your iMac needs a Firmware update. What told you to update Fireware? I know some older iMacs will go BLACK like that after the install of OSX unless you upgrade the Firmware. Purple should be the Grape. It's a 400Mhz for sure? My Grape is a 333 but already had the Firmware upgraded. Will get back to you. Going to check on which models need the upgrade. Is your CDROM a Tray load or Slot Load?

 

[Badger]

If you have a slot-load CD drive then you almost certainly have a video problem not a bad CRT. As noted above, trying to install any version of X on the slot-loaders can cause serious video problems. Here's a link with all the data and how to fix it: http://www.capecodgraphics.com/imac_firmware.htm. The good news is that you can fix it with some effort and you don't need a new CRT.