Atari 600xl 64k memory upgrade methods

[Rybags]

Old ISA graphics cards were good for a while but probably better left now for retro PC building.

Arcade component suppliers should have plenty of them, I'd not pay more than a few bucks per chip at most (though I have a reasonable stash of my own here).

[Wrathchild]

sometimes on some old ISA graphic cards

 

[Edit] Ha, hadn't seen Rybag's post

Edited November 25, 2019 by Wrathchild

[manterola]

What about this guy?

https://www.ebay.com/itm/10x-NEC-UPD41256C-10-D41256-256K-100ns-PAGE-MODE-DRAM-16-DIP/113130079041?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Edit: I am sorry, these are not good for the 600xl without major changes. These that I just posted are 1bit RAM (256k), good for changing those MT damaged ram chips, typically found on 800XL and first revision 65XE.  

 

Edited November 25, 2019 by manterola

[adam242]

On 11/23/2019 at 10:21 PM, hueyjones70 said:

Where is the best source of the xx64 memory chips?

I used to buy them from Jameco, but they no longer list them on their website.

[BillC]

3 hours ago, adam242 said:

I used to buy them from Jameco, but they no longer list them on their website.

I just searched on Jameco:

https://www.jameco.com/z/41464-10-Major-Brands-IC-41464-10-DRAM-256K-Bit-64Kx4-100ns-w-Page-Mode-HY53C464S-10-_41574.html

[adam242]

7 hours ago, BillC said:

I just searched on Jameco:

https://www.jameco.com/z/41464-10-Major-Brands-IC-41464-10-DRAM-256K-Bit-64Kx4-100ns-w-Page-Mode-HY53C464S-10-_41574.html

I stand corrected. Was searching for 4464, not 41464.

[manterola]

When I needed those, I just searched ebay for TMS 4464 and then I just picked one... like this:

https://www.ebay.com/itm/10pcs-TMS4464-10NL-TMS4464-DIP-18-TI/180920063287?hash=item2a1fad1537:g:7RoAAMXQ0pNRvcsR

[+DrVenkman]

Necro-ing this old topic to report that I used @Mathy's instructions linked in one of the posts above to upgrade one of my 600XL's tonight. I know it's an easy mod, but it's still always nice when something works the first time. For the replacement memory, I used some NEC 41464-10 chips I bought on eBay over a year ago. I just never got around to this upgrade until this afternoon.

 

 

[Kyle22]

Solder 3 wires, put in 4464's then install Ultimate 1 Meg.

That will get you going.

Look for the up and coming SIDE3.

 

Edit:Also, do something about the video.

Edited June 26, 2020 by Kyle22

[cwilbar]

I did it the 'hard way' 🙂

 

I modified the system such that no chips are soldered to.  Changes on the bottom, changes under a chip socket or two, and now it's as if it was 64K from Atari.  Chip fails, pop in a replacement chip.

 

In retrospect I think I should have just used the 64K SRAM that IIRC goes between the cpu and socket.  Then you can pull several components from the PCB as they aren't needed anymore.

 

But I still like the way it turned out.... but it was a real pain when I discovered I had to pull one or two chip sockets to separate a connection I didn't know were hiding under there 🙂

 

 

[+DrVenkman]

6 hours ago, cwilbar said:

In retrospect I think I should have just used the 64K SRAM that IIRC goes between the cpu and socket.

I know Lotharek makes one now but even then you need to solder at least one wire to the MMU or a nearby via. His site also said that some upgrades might need you to solder a second wire. Seems to me that if you’re soldering wires anyway, might as well go with the one that’s cheaper - which in this case was these memory chips ($3.09 on eBay last year for a lot of five chips ). 

[+hueyjones70]

I saw a mention of a 256K RAM upgrade on the Best Electronics web site. Has anyone have any experience/knowledge with it?

[hloberg]

here's my write up of adding 64k to my Atari 600XL I just did. Not all that bad to do. I tried to be very detailed.

 

[+slx]

Thanks for sharing and taking the time to document.