Apollo 68040 how to properly install it on a 1200 and close the trapdoor ?

[Pat the Cat]

Apparently if you have only one RAM socket then it will fit into an untowered A1200;-Did the card have another socket added to it?

http://amiga.resource.cx/exp/apollo1260

https://bigbookofamigahardware.com/bboah/product.aspx?id=110

What might be happening is that your simm socket on the top has a loose or dirty fit. Maybe a squirt of DeOxit or WD-40 might clean it out. Even just compressed air from a bicycle pump or something is worth a shot.

Oh yeah, careful what you print the new trapdoor with. PLA not recommended, it will go a bit saggy and sticky over 60C. ("Glass transition point" - not liquid melted but soft.

EDIT: Interesting blog printed fan duct to help with cooling here, but no download I can see. Maybe contact them if interested?

https://amigaalive.blogspot.com/2020/10/new-apollo-124040-cooling-system.html

[Pat the Cat]

Fair play, if the trapdoor is away from the CPU and no 2nd simm slot, trapdoor should fit and printed PLA trapdoor with holes should be fine.

I still think it's a dusty / dirty connection somewhere causing the issue with stability.

[Pat the Cat]

Has it been recapped ever? Board and the A1200?

I'd check out for leaky caps with a bright light and magnifiers.

Also, if you have a floppy drive in the machine, you could try removing it to see if improves stability at all. (They have caps too.

The Max trans thing just reduces the maximum length of file transferred in one go. Probably not that.

Do bear in mind the 68040 isn't very gamer friendly. It's not just games working at all, it's also how they exit back to Workbench..,

.., and what version of 68040.library do you have loaded? Could also be a factor.

EDIT Manual recommendation - don't use a standard power supply. What's it clocked at, 25, 33 or 40MHz? (Half of crystal frequency).
https://bigbookofamigahardware.com/bboah/media/manuals/a_68060.pdf

[Pat the Cat]

The card has done very well to survive considering it was only warranted for component defect, not damage caused or consequenctial losses caused by using it even during the first six months.

Your CF card probably isn't drawing more power than it ever did BUT Psu's often supply less amperage in old age due to decayed caps (there again).

Also the speed you are running it at has a big impact on energy used and heat generated. As things get hotter they draw more power, and if every component is covered in dust they can't help but heat up.

You could have anything in there for all I know (WB3 had one from Commodore, most folks just download);-

https://aminet.net/package/util/libs/MMULib

The latest "just the flipping library fer Gawdz sake" from 2017 is there, BUT there's a whole lot I don't know about which is best for the Apollo card up on Aminet. For instance with whatever version of kickstart (can be done apparently).

The snag with using anything but the library is that it will take up some RAM. Depends on what your Workbench is set up like. MMULib seems greedy. There was a thread in the last couple of weeks about a seperate "just this" version of the 68040.library from Thomas Richter. I'll have a rummage and edit post later.

And to be honest, never had 68040 in a real Amiga. Used a couple but never as a personal machine. I think I had one for abou
t a week in an A2000 at work.

EDIT: These are "light" versions that save about 200K of RAM. They are kind of optional to MMULib.

http://aminet.net/package/util/sys/Mu680x0Libs

Appears to be the same 68040.library in either one from 2017.

MMULib may seem greedy but is adding a reporting system and offers some proection against out of control sofrware crashing the system. That may appeal to you (You'll still have plenty left out of 16MB to run WHDLOAD I think, even with a shadowed ROM).

Both 68040 and 68060 REQUIRE a custom library to work at all. They're optional on 020 and 030 but still have custom libraries in the MMU release. Enforcer? Exception handling for crashes? That's all in there and more.

[Pat the Cat]

A 40MHz 040 sheds over 9W in heat, which is about half your 5 volt rail capacity. I don't know what the power draw all the other chips is too.

The holes in the trapdoor at least allow more cold air in, that's a step in the right direction for cooling at least.

Where it exits the case is also an issue.

The CF card peak drawer is about 100 milliamps, but both it and the floppy drive are fed power over ribbon cables whch add a bit. Even an empty floppy drive needs that or a little more for the circuit board, bearing in mind the relays go "clunk" every few seconds on an Amiga.

The unstable sound might be down to a lot of things. Might be related, might not. Audio needs nice clean + and - 12V to work properly though, it could be related to power.

I think there are a lot of solutions out there for heatsjinks and ducted fan arrangements, not specific to 68040s but maybe adaptable?

I don't even know the voltage of the supplied fan.


You could have a fan on the trapdoor to suck cold air into the case.

EDIT: This project recommends Sunon PMB1212PLB1-A for cooling Xeon's. But it's a blower fan, I think same principle but they would need +12V I think. The ducts for printing aren't relevant I think... Maybe they are. Perhaps a heat sink and a blower fan either side of the chip? That mod I listed had only one.

https://www.thingiverse.com/thing:2623783

[Pat the Cat]

1. Whether the CPU has been damaged or not... compatibility with WHDLoad is often untested on a 68040 or 68060 as far as I can gather from their web page. They recommend 68K as "most compatible", and for deveopers creating new WHDLoad versions of games they recommend at least an 030. That is conjectural, perhaps they test recent slaves or not, you could try talking to them about the issue;-

http://www.whdload.de/docs/en/index.html

2. Pin wisee the sockets  are all the same. Presumably a low profile one rather than a vertical one. Whether that lets  you plug in the trapdoor or not is  the key question. I don't know personaly the answer.

[Pat the Cat]

Not in production currently. Could be lack of 030s or profit margin compared to selling 020 cards.

Only other ones I've heard of are Warp 1260 or Vampire, for the A1200.

Bearing in mind your unit is original, you could get most or maybe even all the cost of a Vampire for it.

Is the 68040 soldered in? Makes it harder to upgrade your card to a 1260 (another option).

You definitely want to shop around for lowest profile socket, mouser have a few (22.5 degrees) but there's probably lower angled simm sockets out there.

[Pat the Cat]

Long shot - have you done any timing fixes to the A1200 motherboard?

http://www.ianstedman.co.uk/Amiga/amiga_hacks/A1200_Mobo_fix/a1200_mobo_fix.html

[Pat the Cat]

It will do no real harm to use the old heat sink, but a square aluminium one would be better, and a copper one would be best. Weigh the cost. DO NOT BUY A HEATSINK THAT IS TALLER THAN THE ONE YOU HAVE - it must fit under the keyboard.


If the heatsink fell off - that would explain why it keeps overheating.

I would be happier replacing it with a copper or brass heatsink (better than aluminium one). A square one to cover the center of the chip, because that's where the die of the chip is. You can use more than one to cover the area, but a single one about 40mm X 40mm offers a fairly good fit.

As for glue to use, look for "thermal conductive adhesive". Germany makes some of the best you can get. There must be shops there selling the glue to overclock enthusiasts. Also, 3D printer shops often stock the products, (because they are used to glue heatsinks to motor controller boards in 3D printers to help keep them cool). Don't be in a hurry, shop around for the best thermal conductivity, low viscosity (most "dribbly"). You will have to make sure there are no air gaps in the join,

As for a "cheap" VGA connection - all the cheap ones rely on the monitor being able to handle Amiga sync rates, which most monitors do not. The expensive external solutions convert the slower signals to a true VGA standard, and the internal ones are even more expensive. A scan doubler works to a point, but will cause a "torn" display on a fast 50Hz game.

I got no answer for you on that one. I could well be wrong too, perhaps there is a cheap scart-VGA adapter on amazon or similar, that works in all Amiga screen modes,

EDIT: What might work is a cheap scart-HDMI converter, then a cheap HDMI-VGA converter. I have tried the latter, they do work, but generaly with high resolution VGA monitors, 17 inch display or larger (must have over 1,000 vertical lines, 1280 X 1024). I don't have any experience with cheap scart-HDMI converters.