exxos's Atari, Amiga & retro forum

exxos wrote: 22 Jan 2022 16:58 Just lift the right hand side of the 68R resistors ( next to MMU ) and tie them to 5v.

Ok, I don't want to come across as facetious, but I want to be totally sure before I start the cutting and soldering. I don't want to damage my ST.

You keep referring to the resistors to lift as 68R, yet in the pic of the silly board that resistor and the ones next to it are untouched.
Now, I can see that in the Mega ST portion of the webpage the lifted resistors indeed are R68 and some others. But it is also evident that for the silly board different resistors were lifted. Unfortunately, the picture is quite blurry and the red cable gets in the way.
All I ask is if you could just please let us know the actual numbers of the resistors to lift for the silly board? Are we talking about resistors 90, 93, 94, and 91, lifted and connected to C89?
Thank you in advance for your kind help!

If you download the manual for Marpet/Frontier Xtra-RAM board it has info about how to deactivate RAM on different motherboards.

I am talking about these:

ppyo wrote: 29 Jan 2022 20:46 Ok, I don't want to come across as facetious, but I want to be totally sure before I start the cutting and soldering. I don't want to damage my ST.

You've confused some terminology. Exxos isn't telling you to remove resistor R68, he's telling you to remove all the resistors that measure 68 Ohms (68R).

There are many different motherboard revisions, each with different resistor numbering schemes. Your best bet is to read the resistor code bands or measure the resistors around the RAM with a multimeter and snip one leg of them.

BW

ppyo wrote: 29 Jan 2022 22:00 I am talking about these:

atari_st_silly_mb_zoom_in_for_upgrade.jpg

4 resistors 68R (value, the ones you circled) , lift the right side of them 4 and tie to 5V.. that's all you do.. The other resistors (33R) don't matter..

It is evident I am no E-Engineer, right?
That is all I need to know. :)
Thank you very much!

Always best to make sure before doing stuff :)

Maybe you can post a new image so I can use it on my site ? Maybe help confusion for others.

:dualthumbup: Will do!