Page 1 of 2

Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 12:36
by mgi
Hi,

While playing with my newly acquired Atari 65XE I noticed very odd issues with certain graphic modes. I googled it and learned about known issue with faulty GTIA chip in a batch of computers in early 90s. There is a test within the SysInfo to help diagnoze the problem and as it happens I have this bad chip. :(

Since this chip is soldered into the motherboard it is a bit of a challenge for me. Does anyone had experience with this? Anyone in UK who could help with sourcing/replacing the GTIA chip? I know there is also a workaround requiring some cutting and adding few wires - also not something I would be attempting on my own if I could find a good soul who could help and who has experience with Atari.

I also found this https://www.ebay.co.uk/itm/125498651221 ... media=COPY - anyone tried this?

Any suggestions welcomed!

Cheers
Michal

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 12:45
by PhilC
@mgi what's the number on the chip? I may have a spare but would need to check.

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 13:43
by mgi
Screenshot 2023-06-06 at 13.39.09.png

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 14:09
by foft
There is a way to work around the bad gtia apparently.
https://atari-owner.com/club/articles/f ... a-chip.57/

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 14:14
by mgi
Yes, I have seen it but I guess when you start cutting traces and adding all the wires you may as well replace the chip with the good one or with this item from eBay I put in my link above. I would need to get the correct socket and desoldering gun before attempting this myself.

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 15:10
by foft
I have a desoldering iron but am in Switzerland.

I think fjc does some repairs and is in the uk, could email him:
https://atari8.co.uk/

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 15:22
by mgi
That's very useful - thanks!

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 15:41
by rubber_jonnie
If FJC can't help, then I could remove the old GTIA and fit a socket for you, presuming you're in the UK.

I don't have a spare GTIA either, but I could test with one of my own before sending the machine back to you. Or if you can supply a GTIA I would be happy to fit a socket and the IC and test. (I have SuperSalt and SYSINFO)

An example of some of my stuff is here: RJs previous work if you want to check out my credentials. You'll find me fixing a lot on this site.

I would be prepared to do the work for free, and just document on the forum, but I would require you to pay postage of the item both ways.

If FJC can't do it, give me a shout.

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 15:53
by PhilC
@mgi I do have one but its got a couple of broken pins, so its likely I kept it for testing only.

Any other chip and I'd got a few of each spare

Re: Atari 65XE Bad GTIA chip

Posted: 06 Jun 2023 15:56
by mgi
This forum is the best - I have no question about it. In few minutes kind people offer to help!
Do you think which chip could still be used?