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RAM upgrade mod atari

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#1 relo999 OFFLINE  

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Posted Mon Apr 10, 2017 5:07 PM

What are the different models that I could best buy?

400 - 8k of 16k machine and can be upgraded by adding extra memory in the slots of the machine. This was marketed as a gaming machine which it's design to an extend shows as it's a light weight 800.

800 - 8k to 48k machine and can be upgraded by adding extra memory in the slots of the machine.

600XL - 16k, 
easy to upgrade (if socketed) by popping in new ram chips and soldering a couple/few wires, depending on the method.  
 

800XL - 64k, the most common - almost ALL software will work on a 64k XL...some 1990s (and onwards) demos and games require more ram. almost ALL Taiwan 800XLs are soldered - which makes upgrading harder. 50% of Hong Kong 800XLs have socketed ram.
 
1200XL - 64k, the easiest to upgrade, but easier to buy in the USA than europe. most ICs are socketed which makes installing a 256k wizztronics clone, Ultimate 1mb or the newer Antonia 4mb upgrades much easier. almost all 1200XLs will need a clear pic, UAV or similar upgarde to make video reasonable.
 
65XE - 64k, an XL with ST styling - many do not have the ECI port.
 
130XE - again, an XL with ST styling, but with 128k ram.
 
800XE - 64k, eastern european crossover from XL to XE range - some (about 30%) of these have a buggy GTIA chip, but if you strike lucky you get a nice "XL" with freddie chip and ECI.

XEGS - 64k, a consolized 65xe.

 

Why upgrade RAM? 
To either gain access to 130XE library and to more modern demo's, games, etc.


Different RAM standards and why do they matter? 
Plain and simple comparability as some RAM upgrades have different memory adresses, which means some software might not run or not run correctly under a different standard.

 

Can and is it worth it to upgrade my RAM by filling out empty RAM spots on the motherboard on my 65xe or 800xe?
Yes, if you have those slots and if you don't want to go all out on the RAM or keep your machine like it was during the machines production life. Watch out for the faulty GTIA's though. You can check for those buy typing in :
 

10 GR. 9:D=1:FOR X=0 TO 79
20 COLOR C:C=C+D:IF C=15 OR C=0 THEN D=-D
30 PLOT X,0:DR. X,191
40 NEXT X
50 G. 50 

And you should end up with something looking like this:
post-7804-1220937145.png or using my own computers as an example: http://imgur.com/gallery/bAOr0

This is how you can upgrade:

 

Which RAM upgrade kits are still available? (mainly available for 800XL and later models, unless noted otherwise)

Ultimate 1MB                                http://lotharek.pl/product.php?pid=67

wizztronics 256K                            http://www.best-elec...onics 2_256.htm

Rambo XL 256k                             https://www.bitsofth...ambo-xl-adapter

512k SRAM-Extension by Mega-hz:  http://mega-hz.de/An.../512K/512k.html

 

Due to some upgrades going through production runs of batches and than going out of production until another is announced these might not be available at the time of reading (You could always try and message the creator if they are available still or in the future):

512k SRAM-Extension by tf_hh:       Write tf_hh a pm here on AtariAge

Syscheck II by tf_hh:                      Write tf_hh a pm here on AtariAge
(only works on 64k machines and higher)

Ctirad 576XE                                 http://atariage.com/...ead/?hl= ctirad
(No soldering required, up to 576k of RAM and please not "up to" as it requires you atari be on 128k of RAM before slotting it in to get that amount, otherwise you won't get 576k)

Incognito                                      Don't know where it is available
(only for the 800)

Antonia 4MB                                 http://atariage.com/...on/?hl= antonia (I assume there is a newer location that sells them that I'm not aware of)
(please note, the Antonia has 2 different versions one for the XL line and the other for the XE line)

(Please note I've excluded older upgrades and self build upgrades, like this, for simplicity reasons, otherwise this would become a very long list)

If you have information to add, rectify or remove, please comment so I can change it.


Edited by relo999, Sat Apr 15, 2017 2:11 PM.


#2 DrVenkman OFFLINE  

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Posted Mon Apr 10, 2017 5:11 PM

Do you want to remain "old school" and do it with discrete DRAM chips? Do you want a PBI plug-in solution? Are you okay with something more modern and flexible like the Ultimate 1MB? We need some paramters to help you narrow down the possibilities.



#3 relo999 OFFLINE  

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Posted Mon Apr 10, 2017 5:33 PM

I don't care either way about modern-ness. But I think before going on a hunt to find the right upgrade I think it's important to know why to upgrade, which is something I can't find any info on. Case and point, the U1MB seems quite useless to me in the vast majority of cases but it seems to be a quite common mod so there is probably a good reason why that is (aside from availability I reckon).

My main question is thus why upgrade and what are the options listed out. That info is seemingly hard to come by, which I find weird, as I can only find the occasional mention of a specific upgrade(aside from the U1MB, which seems to be really common).



#4 DrVenkman OFFLINE  

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Posted Mon Apr 10, 2017 5:54 PM

Speaking for myself, I installed a U1MB in my main daily machine for a number of reason, not just the extra RAM - but having said that, having a megabye that I can use in several different ways allows me to both run software that can use the XE bankswitching scheme, but also tons of demos that have come out over the last 30 years that require 128K or more. Further, I can use the extra memory as a nice-sized ramdisk. To someone like me who grew up using a 1K ZX-81, a 16K Atari 400 and then a luxurious 48K of my Atari 800, these are reasons enough.

 

But if you go the U1MB route, there are other benefits: first, it's super easy to install - two ribbon cables that plug into existing sockets in XL machines (some later models and the XE machines might require desoldering chips), plus four easy wire jumpers to solder to via points on the board. Second, the U1MB lets you select from four different OS roms for your particular needs, 4 versions of BASIC (or any other 8K rom you might want to use), and optionally 4 XEGS game roms if you use an XEGS OS and set a jumper on the U1MB board. 

 

There are more benefits - especially if you use it with Flashjazzcat's "alternate" firmware and/or an IDE device like a SIDE2 cartridge - but for most people's day to day needs, these are the highlights. 



#5 AlecRob OFFLINE  

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Posted Mon Apr 10, 2017 6:06 PM

Still trying to figure out how to install a Rambo board in a 65XE NTSC system... i get the feeling it's possible somehow...

#6 relo999 OFFLINE  

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Posted Tue Apr 11, 2017 2:22 AM

The RAM upgrade seems to be the main bonus, the others seem to me more as nice bonuses for someone like me who'll probably only be using it to play games and run some demo's.

So what would be some other options to upgrade the RAM? And would it be smarter for me to upgrade the 800XE instead of the 800XL due to XE bank switching?



#7 DrVenkman OFFLINE  

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Posted Tue Apr 11, 2017 5:49 AM

The RAM upgrade seems to be the main bonus, the others seem to me more as nice bonuses for someone like me who'll probably only be using it to play games and run some demo's.

So what would be some other options to upgrade the RAM? And would it be smarter for me to upgrade the 800XE instead of the 800XL due to XE bank switching?


Well if you upgrade memory using the U1MB, you can set the memory to Stock, 328K Rambo, 576K Compyshop or 1088K Rambo configurations. In other words, it doesn't matter which system you put it into. The U1MB replaces the stock MMU chip as well as the OS ROMS.

#8 relo999 OFFLINE  

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Posted Tue Apr 11, 2017 6:37 AM

What's the real differences between those memory modes aside from size? Compatibility with bank switching?

And are there any other RAM upgrade possibilities aside from the U1MB, that probably aren't as feature rich? 
Is, for instance, upgrading the 800xe to 130xe levels useful? And if so, are the chips for that still available without paying an arm and a leg for NOS.
 



#9 orpheuswaking ONLINE  

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Posted Tue Apr 11, 2017 7:02 AM

It's extremely easy to upgrade an 800XE to a 130XE as it's basically the 130XE board missing components. Most of which are still fairly easy to obtain. If you go beyond that the options are numerous so it is really hard to give you an answer. 



#10 relo999 OFFLINE  

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Posted Tue Apr 11, 2017 7:47 AM

It's extremely easy to upgrade an 800XE to a 130XE as it's basically the 130XE board missing components. Most of which are still fairly easy to obtain. If you go beyond that the options are numerous so it is really hard to give you an answer. 

Ahh, good to know. Any info on where I could find a tutorial or some document how?

Yea I noticed that, which is why I asked. Been doing research of and on for 2 days now and still don't seem to have a real clue on what might be an good option, where to get them or what the differences are between them and what options are out there. Reason being that I haven't jumped on a U1MB yet is simply price and usefulness, for me it seems to be overkill for what I want to do with my atari's, so tossing 65 euro's at it seems to be a waste to me. Which is also why I ask what the use is of the RAM upgrade, because if, say, 64k or 128k is enough to run nearly everything with the exception of 5 or so demo's and games than getting more memory than that seems to be not very useful.

All in all RAM upgrades just seem very confusing for the Atari 8 bits compared to any other computer I've noticed. Which is also why I try to get as much info in one thread as that info in one pace might be useful for others that are in the same situation as I am in now.



#11 SoulBuster OFFLINE  

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Posted Tue Apr 11, 2017 8:29 AM

2 additional features of U1MB, Sparta Dos X and a Real Time Clock are built in.



#12 AlecRob OFFLINE  

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Posted Tue Apr 11, 2017 8:34 AM

https://imgur.com/gallery/2FH8o

Pics of the unit I'm trying to upgrade.

So, no way to get a Rambo on here like on an 800XL?

#13 ClausB OFFLINE  

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Posted Tue Apr 11, 2017 4:21 PM

That has a Freddie chip instead of LS158s but I'll look into modifying the 256K upgrade to match.



#14 AlecRob OFFLINE  

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Posted Tue Apr 11, 2017 11:46 PM

That has a Freddie chip instead of LS158s but I'll look into modifying the 256K upgrade to match.

 I actually have one of the reproduction rambo boards from Lenore, and so i have been researching ways to get it running on my 65XE... but if that never works i'll just put it in an 800XL...  Definitely let me know your findings...  



#15 1050 OFFLINE  

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Posted Wed Apr 12, 2017 4:27 AM

Used to be tons of this info out there, but today is a different story
as declared.

http://ftp.pigwa.net...Memory Upgrade/
http://ftp.pigwa.net...Ram Extensions/

Those have done a pretty good job of collecting some and archiving
them.

#16 kheller2 OFFLINE  

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Posted Wed Apr 12, 2017 6:28 AM

. Which is also why I ask what the use is of the RAM upgrade, because if, say, 64k or 128k is enough to run nearly everything with the exception of 5 or so demo's and games than getting more memory than that seems to be not very useful.
All in all RAM upgrades just seem very confusing for the Atari 8 bits compared to any other computer I've noticed. Which is also why I try to get as much info in one thread as that info in one pace might be useful for others that are in the same situation as I am in now.


Please clarify how RAM upgrades on other computers is less confusing? In general, today's Atari upgrades aren't just RAM upgrades: they are functionality upgrades that include a RAM upgrade (or completely replace the stock RAM).

RAM gives you the following:
The ability you to play everything officially released and have more space for, say, word processing and coding. Having DUP/DOS in RAM was a great time saver.
Additional RAM let's you play more recent demos
RAM gives you the ability to have RAM disks and do one pass disk copies.
Modding is fun.

In your case it seems you would be well suited just enabling the full RAM features of the 800XE and turning it into a 130XE using period relevant components.

#17 relo999 OFFLINE  

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Posted Wed Apr 12, 2017 9:47 AM

Please clarify how RAM upgrades on other computers is less confusing? In general, today's Atari upgrades aren't just RAM upgrades: they are functionality upgrades that include a RAM upgrade (or completely replace the stock RAM).

RAM gives you the following:
The ability you to play everything officially released and have more space for, say, word processing and coding. Having DUP/DOS in RAM was a great time saver.
Additional RAM let's you play more recent demos
RAM gives you the ability to have RAM disks and do one pass disk copies.
Modding is fun.

In your case it seems you would be well suited just enabling the full RAM features of the 800XE and turning it into a 130XE using period relevant components.

Well in most cases it's just one type of upgrade with very little in the way of different versions (like RAMbo, Compyshop and I heard a few others). Normally an RAM upgrade is just that, a RAM upgrade not a RAM upgrade that has a specific version and can do more than just be RAM. And than there is a apparent lack of communication on the subject especially for people trying to get in without seemingly needing to know a guy. There is a lot of talk about RAM upgrades, but seemingly non on the most basic information things like the what, why and how. Which I find especially weird considering how seemingly common a RAM upgrade is, as other machines with similar popularity have multiple guides to their common mods.
There is simply not something along the lines of a "guide to RAM upgrades" or something along those lines. It's just extremely hard to get my head, as someone new the Atari 8 bits,  around and find info on what's available, whats useful, what the differences are, where to get it and how to install it.


As for modding is fun, it definitely is. Which was one of the reasons why I wanted to a RAM upgrade to begin with, as my other consoles and computers are already to the point that there aren't any useful mods to do on them. 

How would I make my 800xe into a 130xe? Would it be possible to do the same to 800xl? 



#18 kheller2 OFFLINE  

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Posted Wed Apr 12, 2017 1:35 PM

AFAIK, 800XE's are just 130XE's minus the extra bank of memory and possibly the EMMU (CO25953). I don't own one. They also had bad GTIAs in some batches.

 

How about sharing a picture of your mobo?  If you have an ECI port, you have some version of the 130XE board.  I'm assuming all you need to do is fill in the missing RAM slots, swap in the EMMU and maybe a wire or two and be done.

 

As for pure RAM upgrades, the differences are in the size, obviously, but also in the bank switching sizes and methodologies.  (16k, 32k, etc.. Antic and/or 6502)

 

Supposedly you can take an 800XL add an EMMU and another set of ram chips, have a 100% identical 130XE, minus the ECI, REVC Basic etc..

 

We are also specifically talking about XL/XE RAM expansions.  400/800 is a different thing all together. 

 

(Rambo vs CompyShop: http://atariage.com/...-etc/?p=2729804 )



#19 orpheuswaking ONLINE  

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Posted Wed Apr 12, 2017 1:38 PM

800XE -> 130XE Usually very easy as they use the same motherboard, the 800XE is just missing half the memory, the EMMU and (I believe) some resistors (it's been awhile) I would also verifiy if the GTIA chip is one of the bad batch or a good one. 

 

800XL -> 130XE harder and requires a physical mod of some description as the motherboards are completely different. 

 

[edit] 

 

kheller2 beat me to it :D


Edited by orpheuswaking, Wed Apr 12, 2017 1:39 PM.


#20 relo999 OFFLINE  

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Posted Wed Apr 12, 2017 3:23 PM

Ahhh alright, that makes sense. I know mine is a 130xe board, dunno what batch though, but I'll send a photo of the mobo as soon as I can. I also remember the mobo of my 800xl is Taiwanese and don't remember it having sockets (so probably a nice desoldering job, if I want to replace that). What are some good identifiers of the board I should take photos of?
 

What if I want to go beyond that the 256k, now or in the future, what would than my options be beyond the before mentioned U1MB?

"minus the ECI"
That's just in the PBI right? Or are there special things you need that for?

As for 
Rambo vs CompyShop that is just compatibility right? Or are their no real differences?

(I'm so glad I made this topic rather than keep looking)
 



#21 kheller2 OFFLINE  

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Posted Wed Apr 12, 2017 4:15 PM

Ahhh alright, that makes sense. I know mine is a 130xe board, dunno what batch though, but I'll send a photo of the mobo as soon as I can. I also remember the mobo of my 800xl is Taiwanese and don't remember it having sockets (so probably a nice desoldering job, if I want to replace that). What are some good identifiers of the board I should take photos of?
 

What if I want to go beyond that the 256k, now or in the future, what would than my options be beyond the before mentioned U1MB?

"minus the ECI"
That's just in the PBI right? Or are there special things you need that for?

As for 
Rambo vs CompyShop that is just compatibility right? Or are their no real differences?

(I'm so glad I made this topic rather than keep looking)
 

 

 

XE ECI PORT + CART PORT ~= XL PBI

 

"real" RAM differences?  Depends what you mean by real.  The way banking works varies. That is the major difference. 

Historically you have three "commercial" bankswitching methods:

130XE

RAMBO

NEWELL

 

Then toss in the plethora of home made / free ones.

 

There used to be a listing of most of the old school RAM upgrade's and how they worked.  Most of the new RAM add-ons can run in various legacy style modes.  IE, you want RAMBO mode, ok... you want NEWELL mode.. ok..

 

There are even RAM upgrades out there that take you to 512 with a battery backed SRAM for keeping your contents alive when the computer is off.

I've see 1024K as well...up to 4MB and various ways of doing that from DIPs to DIMMs and SIPPs and magical crystal storage of the future.

 

Typically, 256K is enough for the medium-heavy user.



#22 kheller2 OFFLINE  

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Posted Wed Apr 12, 2017 4:18 PM

Lifted from "The Atari 8-bit Hardware Upgrade, Modifications and Add-On FAQ" circa 1996.  Not corrected.

 

Atari 1200xl

See 800xl.

Atari 600xl

As shipped, the Atari 600xl came with 16k RAM. Atari
released the 1064 memory module which expanded the 600xl to 64k.
MPP, now Supra, produced the Microram 64k Memory Board (ANL 19,
28)

RC Systems produced three expansion modules for the 600xl,
raising memory to 32k, 48k or 64k (ANL 26, 12)

Richard Gore produced the Yorky, a 256k board which plugs in
to the PBI. It provides full compatibility with 130xe type
banking. It is for use on 600xls upgraded internally to 64k, or on
800xls. (AC 3/2, 10)

Atari 800xl

The Atari 800xl came with 64k RAM internal. To access RAM
hidden under the OS ROMs, the PIA chip was used (PORTB, used for
STICK(2) and (3) on the original 800). Claus Bucholtz published
plans for a 256k upgrade which banked 32k at a time using PORTB for
control in Byte magazine. (Byte Sept 85)

ICD released the RAMBO upgrade, providing 256k in 16k banks,
using PORTB. Newell came out with the 256k XL, which would work on
a 1200xl or 800xl, providing 256k total memory, . The two upgrades
used different sequences to access their banks. (ANL 44, 115)

Charles Bucholtz updated his upgrade to use 16k banks after
the release of the 130xe. Most of the 800xl upgrades can be made
compatible with Antic banking. The only possible problem would be
when Antic and the CPU are supposed to be using different memory
banks.

The Yorky will also provide 256k on an 800xl (see the entry
under 600xl).

Other PD upgrades give plans for adding a second row of 256k
RAM chips, raising the 800xl to 512k.

Newell released 1Meg and 4Meg upgrades for the 800xl. These
banked 16k as well, and required disabling internal BASIC to
properly access the memory.

Klaus Peters also released 1Meg and 4Meg upgrades for the
800xl.

Fine Tooned Engineering, having bought the rights to ICD and
Newell's products, is bringing out a third method in the Mars 8.
Though not yet released, it will use SIMMs for 256k, 1Meg or 4Meg
RAM.

The 800xl is arguably the most popular Atari 8-bit for
upgrades, since most 800xls have socketed chips.

Atari 130xe

The 130xe was the first "official" method of banking memory.
It too used PORTB, but with an added twist: ANTIC and the CPU could
access different banks. This provided headaches for some owners of
"older" upgrades, but few programs took advantage of this feature
(SpartaDos Wedge and VideoBlitz demo only). Upgrades for the 130xe
include replacing one set of 64k chips with 256k chips, raising the
RAM to 320k. Adding another 256k for 576k total has also been
done. These were designed by Scott Peterson, as was a 1088k
upgrade.



#23 DrVenkman OFFLINE  

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Posted Wed Apr 12, 2017 4:18 PM

 

As for Rambo vs CompyShop that is just compatibility right? Or are their no real differences?
 

 

They are two competing standards for bankswitching RAM upgrades beyond the usual 64K an 8-bit processor can address directly. The differences matter for certain software that is written to take advantage of one standard or the other. Predominantly it only matters for playing demos and certain productivity software written for one or the other.  The benefits of a modern, configurable solution like the U1MB or the more recent Antonia 4MB is that it can be configured to function however you like via a firmware menu, and when you need another configuration all you do is reset or reboot back to the menu and change it.



#24 CharlieChaplin OFFLINE  

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Posted Wed Apr 12, 2017 4:29 PM

Well,

 

the early 130XE and 800XE boards were different - from 1985-1987 (maybe also 1988 and 1989) Atari used 130XE boards with 16 RAM chips (8kbytes each) and 800XE boards with 8 RAM chips (8kbytes each); thus if you have such an older 800XE it cannot be upgraded so easily to 128k; afaik the 65XE was not available in Europe (or at least Germany) at that time.

 

From 1988/1989 until 1992 Atari sold the 65XE (EU+US), 130XE (EU+US) and 800XE (only in EU) with the same 130XE board that had space for 4 chips (32kbytes each), all four chips were available in the 130XE for a full 128k, whereas the 65XE and 800XE had only two chips (2x 32kbytes = 64kbytes) and two empty spaces (plus an empty space for the Gate Array). Afaik, most if not all of these later XE models with 32k chips were made in China and have the faulty GTIA chip... Thus if you upgrade such an 800XE (or 65XE) to 128k, you do not only require the missing RAM chips, but also the Gate Array and errm, a good/working GTIA...



#25 relo999 OFFLINE  

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Posted Thu Apr 13, 2017 6:14 AM

"real" RAM differences?  Depends what you mean by real.  The way banking works varies. That is the major difference. 

If they are compatible with each other, meaning 256k of Compyshop can run the same programs as RAMbo could with the same amount of memory. But going by what DrVenkman said it seems to be the case that they aren't fully at least.

If nobody minds I'd like to add a section in the first post to create a basic FAQ for RAM, both for personal reference and also for others looking into it. Basically with the "Why upgrade RAM?", "Different RAM standards and why do they matter?", "Can and is it worth it to upgrade my RAM by filling out empty RAM spots on the motherboard?", "Which RAM upgrade kits are still available?" And I'll avoid talking about self build RAM upgrades and legacy upgrades as that confuses things more than necessary but still mention them.

For everybody if you know any still available kits please post them and where to get them, the only ones I know of are U1MB, Antonia 4MB and wizztronics 256K board.

As for myself I'm still undecided but I think I might go for my 800XE upgrade (if at all possible/decently easy and cheap to do) and maybe later a U1MB or Antonia in my 800XL. At least now I feel like I know enough about RAM upgrades to make a half decent decision, although I still feel  as if there are RAM kits that are still available that I don't know the existence of.
And I found this on upgrading the 256k for a 800XE that is detailed enough to easily work from: 

And tonight I'll try to post board pics.







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