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At this time it is unfortunately not possible to white list users when your IP changes constantly.
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So I suggest people only use fixed IP address devices until I can think of a solution for this problem!
At this time it is unfortunately not possible to white list users when your IP changes constantly.
You may inadvertently get banned because a previous attack may have used the IP you are now on.
So I suggest people only use fixed IP address devices until I can think of a solution for this problem!
Trouble pushing 4MB MMU board into socket
Trouble pushing 4MB MMU board into socket
I'm installing the ATARI ST/F/M MEGA ST 4MB MEMORY UPGRADE [0035] from the Exxos Shop.
However, the MMU board won't snap into the socket. I've applied quite some pressure but I don't want to break anything so I didn't use force.
I've tried wiggling the board a bit while applying pressure but the pins don't move at all.
I have the supplied inner bracket in place for protection and I'm sure it is not blocking anything.
Could it be that my socket is incompatible with the upgrade board?
My ST's motherboard is the CO70789-001 REV C1 revision.
However, the MMU board won't snap into the socket. I've applied quite some pressure but I don't want to break anything so I didn't use force.
I've tried wiggling the board a bit while applying pressure but the pins don't move at all.
I have the supplied inner bracket in place for protection and I'm sure it is not blocking anything.
Could it be that my socket is incompatible with the upgrade board?
My ST's motherboard is the CO70789-001 REV C1 revision.
Re: Trouble pushing 4MB MMU board into socket
I'm not aware of any incompatible sockets.. Are you sure you have the pins correctly aligned as shown in the install guide?
- rubber_jonnie
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Re: Trouble pushing 4MB MMU board into socket
I doubt it is the socket, but you never know, can you please post photos of the socket and upgrade parts please so we know what we're dealing with.sandord wrote: Fri Sep 26, 2025 4:48 pm I'm installing the ATARI ST/F/M MEGA ST 4MB MEMORY UPGRADE [0035] from the Exxos Shop.
However, the MMU board won't snap into the socket. I've applied quite some pressure but I don't want to break anything so I didn't use force.
I've tried wiggling the board a bit while applying pressure but the pins don't move at all.
I have the supplied inner bracket in place for protection and I'm sure it is not blocking anything.
Could it be that my socket is incompatible with the upgrade board?
Also, you should always remove the mapnboard and place it on a piece of cardboard on a flat surface to ensure the board cannot flex during installation. I don't know if you did or not, I'm just saying as flex can kill thes mainboards.
I had it happen when pressing something into the Megabus socket on a Mega ST, it damaged 2 vias as the board flexed when I did it.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Re: Trouble pushing 4MB MMU board into socket
I've tried adding photo's to the post but they all turn out black even though I've kept their sizes below 900 MiB. I've tried jpg and png.
Thanks for the tip of removing the entire motherboard, I'll do that.
Thanks for the tip of removing the entire motherboard, I'll do that.
Re: Trouble pushing 4MB MMU board into socket
Yes, they are correctly aligned. All the pin numbers are in line.exxos wrote: Fri Sep 26, 2025 4:54 pm I'm not aware of any incompatible sockets.. Are you sure you have the pins correctly aligned as shown in the install guide?
- rubber_jonnie
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Re: Trouble pushing 4MB MMU board into socket
No worries.sandord wrote: Fri Sep 26, 2025 5:00 pm I've tried adding photo's to the post but they all turn out black even though I've kept their sizes below 900 MiB. I've tried jpg and png.
Thanks for the tip of removing the entire motherboard, I'll do that.
Are you adding the photos as attachments or trying to link to somewhere else? The only supported way here is to use attachments.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Re: Trouble pushing 4MB MMU board into socket
I'm adding (inline) attachments. Here's one. Maybe it's only black in my browser?rubber_jonnie wrote: Fri Sep 26, 2025 5:03 pmNo worries.sandord wrote: Fri Sep 26, 2025 5:00 pm I've tried adding photo's to the post but they all turn out black even though I've kept their sizes below 900 MiB. I've tried jpg and png.
Thanks for the tip of removing the entire motherboard, I'll do that.
Are you adding the photos as attachments or trying to link to somewhere else? The only supported way here is to use attachments.
Re: Trouble pushing 4MB MMU board into socket
It turned out I had to use Chrome instead of FireFox.
- rubber_jonnie
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Re: Trouble pushing 4MB MMU board into socket
That spacer looks far too thick to me, will it plug in without?sandord wrote: Fri Sep 26, 2025 5:13 pm It turned out I had to use Chrome instead of FireFox.
ram6.jpeg
ram5.jpeg
ram4.jpeg
ram3.jpeg
ram2.jpeg
ram1.jpeg
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
- rubber_jonnie
- Site Admin

- Posts: 13811
- Joined: Thu Aug 17, 2017 7:40 pm
- Location: Essex
- Contact:
Re: Trouble pushing 4MB MMU board into socket
I can't see that pic, might be because it's a PNG.sandord wrote: Fri Sep 26, 2025 5:07 pmI'm adding (inline) attachments. Here's one. Maybe it's only black in my browser?rubber_jonnie wrote: Fri Sep 26, 2025 5:03 pm
No worries.
Are you adding the photos as attachments or trying to link to somewhere else? The only supported way here is to use attachments.
mmu.png
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...