Random kickstart screen inverted, possible fault?

[lowlytech]

I drug my A2000 back out to try and get my system straightened out and I have this random issue where the KS Screen colors are messed up. Any idea's what may be causing this? It happens randomly with or without my GVP '30 accelerator. Have a rom switcher and both roms seem to be affected. If I boot an disk, the workbench screens straighten up and look normal. Moving or bumping the system doesn't cause the screen to instantly change, it has to be power cycled to clear up if it decides to that boot. Otherwise everything else seems totally normal. This is connected via 23 Pin RBG to the 1084S monitor.

Thanks for any suggestions.

[Snoopy1234]

There is a similar issue with some accelerators or ram expansions when using Relokick on my A1200. IFAIK it's a ram addressing issue in that case.

[lowlytech]

So you haven't ever had issues outside of the KS screens then with your video anomaly on your 1200? In other words once your program comes up everything looks normal?

This happens with no ram expansion just the 1 Meg of onboard memory, but it seems a lot more noticeable with my 030 Accelerator installed that has 16MB of RAM.

Just wanted to make sure I didn't have some underlying issue that was gonna be left unfixed.

It was suggested too to look for oxidation on Denise or Agnus, and I have cleaned the sockets and chips with DeOxit and the pins look really shiny and good.

[Snoopy1234]

The issue that I have is with the A1200, ACA icomp cards and Relokick. In this case some software doesn't run properly either.

Relokick relocates the rom (in this case a file) into fastram. Are you using Fastrom or some other re-mapper to relocate the kickstart rom?

[eXeler0]

Just gonna mention this to get it out there. One of my A2000s was acting weird with glitchy graphics until I noticed Denise chip had gotten loose and needed to be re-seated.

[lowlytech]

Originally Posted by Snoopy1234

The issue that I have is with the A1200, ACA icomp cards and Relokick. In this case some software doesn't run properly either.

Relokick relocates the rom (in this case a file) into fastram. Are you using Fastrom or some other re-mapper to relocate the kickstart rom?

As far as I know which isn't a whole lot about Amiga's, but everything is basically stock and this happens. I have a ROM switcher daughterboard that has 2 physical ROM's and I can jumper between them.

[lowlytech]

Originally Posted by eXeler0

Just gonna mention this to get it out there. One of my A2000s was acting weird with glitchy graphics until I noticed Denise chip had gotten loose and needed to be re-seated.

Good call, I happened to have an extra Denise and swapped it out completely but the problem still remained.

[lowlytech]

Not 100 percent certain yet, but I think my rom switcher may be where I am gonna focus. It is a Switch-itt/Wilcom ROM Switcher and it seems when I remove it I haven't had the inverted colors after testing it for a few hours.

[lowlytech]

Well nevermind. After being totally fine for 2 hours it did the color inversion when the 1.3 Rom was directly in the socket, so isn't the ROM switcher.

[Liqourice]

Have you checked for corrosion? It sounds a bit like there might be bad contact somewhere.

[lowlytech]

Originally Posted by Liqourice

Have you checked for corrosion? It sounds a bit like there might be bad contact somewhere.

The board is very clean, but I always suspected the sockets having a poor connection. I am not sure but I may have found the fault, but don't want to be too optimistic yet.

I noticed it would almost always invert or change colors when it had been left on for an hour or so to warm up. I felt all the IC's but none of them were remotely hot. However I took cold spray and noticed once I sprayed Agnus it would always clear back up. After doing this about 6 times and it always was consistent, I pulled Agnus out and the socket and chip looked very shiny. I had another 2000 board so I swapped out the chip and have had it on for about 2 hours and randomly restarted it and haven't had it change colors yet.

If it is the Agnus chip, I don't know how serious this is, since even when the KS screen has messed up colors, the moment you booted a game, outrun for example, it would always look perfect with no issues for hours just letting it sit. So it is almost like some line in the Agnus is not resetting when it is first powered up maybe?

Plan to keep this out on the bench for a few more days and I will leave it on overnight and check it in the morning and report back.