Trouble with upgrading a GVP G-force 030

[Viserion]

Got myself an A2000 Rev6 with a said card installed at 25MHz with both 2x4mb ram, and 3x4mb ram.

I'm trying to upgrade the card from the 25MHz cpu it came with, to a 50MHz version. The cpu it self is a 40MHz, but the seller at Amibay has tested it for 50MHz.
I do not have a 40MHz crystal to test with.

I got the 50MHz crystals today, and took out the 25MHz one, and moved it to the FPU spot, as I have an 6882 FPU @25MHz(50MHz version on the way).

I have also tried taking FPU with crystal out, but makes no difference.

Moved jumper so pin 1 and 2 is closed as according to jumper settings this should give sperate speed for CPU and FPU. I also opened up J3 for MMU support.

Also moved various jumpers, including those mentioned above, around a bit in an attempt to solve this.

There are 4 various things that happens when trying to start the A2000.

I know the Amiga is good, as I have used it for several weeks. I also have run the 40MHz cpu on 25MHz for a week or so, with no problems.

There was also other cards, but those I have removed to simplify things.

Some times when it starts the power light blinks 6 times, and continuous to do so until I shut it down.

Some times the I get the kickstart screen( rom 3.1 installed) with red screen telling me the card is faulty.

Some times the screen remains black, and finally when moving jumper J12 from 2-3 to 1-2, it boots, but no extra ram is detected, and when trying a game it didn't seem to run faster than stock 68000 cpu. Didn't have ram enough to boot up to WB, from the SCSI hdd I have installed.

As I'm a bit afraid of taking the CPU card in and out because of danger of causing wear on the card and zorro slot.

That is why I ask here if any one knows what the jumpers needs to be to get this working as it should.

[hese]

Here are some pictures of jumper settings of cards running at different speeds.

Boot problems you describe sound like timing issues, the card is running at faster speed than what it was meant for. Faster cards (40/50 MHz) came with 4MB onboard memory instead of 1MB, maybe they also had other differences that was needed to cope with faster speeds (updated PALs, MACH, ...). I suggest you to get some slower oscillators (33MHz, 40MHz) and try if the card works any better with them. Jumper settings probably isn't the problem.

What is the revision of the 40MHz 68030 CPU?

[voxel]

what model/revision your gvp card is ?

there was a bunch of revisions made by gvp and all the jumpers are not the same among revisions...

[Viserion]

Before I started this, I searched, and came across a thread on a forum, where someone claimed to have upgraded a 25MHz to either 40MHz or 50MHz.
Can't find the link again however.

I also forgot to mention than I am running the Guru rom that I bought the PCB of from someone at Amibay.
It runs fine on 25MHz, and also ran fine on the ImpactII I have for my a500.

I don't think this is the problem, but wanted to mentioned it.

It doesn't clearly state what revision it is. It looks most like rev3, as it doesn't have the metal shield around the CPU/FPU area, but the colour (dark green) is the same as the rev 4 hese linked to.

There is a sticker above the FPU crystal, that says 1.03, and on P/N number the last numbers are '-03' so I would guess it is a rev 3.

I have ordered a 40MHz crystal, but should probably get a 33MHz as well.

It's a 09C74N MC68030RC40B CPU. It's supposed to be a good revision, but I'm not that knowledgeable about revisions.


Added a few pictures. They can be seen here
I have changed the jumper settings back to 25MHz.

[Viserion]

Got the 40MHz crystal today, and while I can get to the KS screen sometimes, I'm unable to boot normally from HDD.

Some times the power led blinks, other times the screen remains black.

Other times I get error messages like the ones below.

IF

Program failed (error #80000008)
Wait for disk activity to finish

C:Version
Program failed(error #8000000B)
Wait for disk activity to finish.



Both have the choice to either Suspend or Reboot.

I also notice the accelerator board is warmer than before. Not so it is unpleasant to touch but warmer than before.

I'm a bit annoyed with it all as I now have both CPU and FPU that should handle at least 40MHz, but is very unstable.

There is also problems detecting the HDD for some reason. Sometimes there, other times not.

Not been able to figure out why.

So unless someone can come with something that solves this, I think I will change back to 25MHZ, and grumble about the cost, and wasted time.

[Viserion]

After taking a break for a few days, I have in found links to post that tells me that the 25MHz version can't be converted to 40 or 50MHZ as the PALs on the 25MHz version aren't up to the task.

See third post in this link, and here is maybe the post that made me believe it was
possible

Is there a possibility to change the PALs to faster versions. In case it is possible, what PALs would I need.

For the record, Sysinfo, never recognized that the new CPU had MMU. Opening or closing J3 made no difference.


As of now, I have no idea if I have broken the G-force or not, as when trying to revert it back to 25MHz the A2000 does not boot properly.

Power light go on, and I can see the Indivision start up screen, but after that everything was dead.

Very strange as the A2000 was always good as gold when removing the add on cards.

After some hours of trying to track down the problem, I caved in, and took the MB out of the case.

Good thing that I did, because after looking for dodgy caps or resistors, I could see that in the CPU Fast slot, 3 or 4 of the connectors was bent so they connected to the other side.

I manage to unbend them to a certain degree, at least so they didn't make contact any more, and that solved the boot problem.

The last problem is then to try to repair the CPU Fast slot.

I guess finding a new one would be a challenge (to say the least), but is it possible to desolder the broken connectors inside, and then replace them with new ones.

Is it possible to get new ones, but if not then I would have to sacrifice one of the other slots, to use the connectors to repair the Fast CPU one.

[hese]

Originally Posted by Viserion

Is there a possibility to change the PALs to faster versions. In case it is possible, what PALs would I need.

Realistically the only way is to take them from a 40/50MHz card. The PAL chips are read protected so you can't duplicate the code inside the chips. Well, by brute force you possibly could but that's another story.

Originally Posted by Viserion

Is it possible to get new ones, but if not then I would have to sacrifice one of the other slots, to use the connectors to repair the Fast CPU one.

You can get new 86 pin connectors from Digikey. You can also desolder and push/pull the needed pins from another connector and replace the bad ones of the CPU connector.

[Viserion]

Originally Posted by hese

Realistically the only way is to take them from a 40/50MHz card. The PAL chips are read protected so you can't duplicate the code inside the chips. Well, by brute force you possibly could but that's another story.

Okay, will have to ditch that idea then.

You can get new 86 pin connectors from Digikey. You can also desolder and push/pull the needed pins from another connector and replace the bad ones of the CPU connector.

Thanks a lot for the link. Will order it from Digikey, as I need to order some stuff there any way.

[idrougge]

It is not advisable to upgrade a G-Force. You're effectively overclocking the Mach and PAL chips to speeds they weren't rated for.

[Viserion]

I found that out myself after a while. Got another one later that was 40MHz version.