RAM in color station turbo

I replaced the ram in color turbo station from 4 x 8 mb SIMMs (together 32MB)

memory socket 0 and 1 (front) have 8 MB ...

memory socket 0 and 1 (back) have 8 MB ...

memory socket 2 and 3 (front) have 8 MB ...

memory socket 2 and 3 (back) have 8 MB ...

to two new RAM SIMMs that I do not know the size, but when I type "m" in Monitor window it says:

memory socket 0 and 1 (front) have 32 MB ...

memory socket 0 and 1 (back) have no SIMMs installed (0x0-0x0)

memory socket 2 and 3 (front) have 8 MB ...

memory socket 2 and 3 (back) have 8 MB ...


Is that OK? Computer works and it is 48 MB now..  but why is there -that no simms installed in memory socket 0 and 1 (back)?

How much ram does the machine report when you boot in verbose?, AFAIK you need to install ram in pairs of the same density.  My Turbo Cube recently reported that it had 64mb when I know it has 128mb, when I checked one simm had come unlatched and was not pressing fully on the contacts in the socket.

Looks like you have ram mismatched to me, try installing two pairs at a time to identify what you have and then try and match the pairs to suit.  I'm not 100% sure but I think you only have to match density per bank not for all 4 simm sockets so you could have 2x16mb and 2x8mb etc.

Is it FPM memory?

machine reports 48 MB, both are the same, like you see in the pictures below and they were not unlatched..






em.. I really do not know what is FPM and how do I know if it is?

FPM is fast page memory. There's some numerical Code on the chips to recognize FPM (if I remember it right it has to be a number with zeros on the end like for example 4100, not so good would be for example 4321).

When I got "new old" RAM I had a look at the number on the chips, then put it for a short test in an old 68K Mac. When the Mac was able to start/run it seemed to be FPM and worked in the NeXTs too most of the time.

nc

I have a Quadra 650 and usually check ram in that first in case of any problems, I'd rather fry the Quadra than the NeXT as it's much easier/cheaper to replace the Quadra mobo.

NeXT's are supposed to use FPM memory, there is another type of 72pin simm that's called EDO (Extended Data Out) which seems to have come out when Pentiums did, people say it works fine in NeXT's, I never tried it, but you might want to make sure you're not dealling with that.

Beware that some special 72pin simms are 3.3 volts (Cobalt Qube II) though I have used 5v in place of 3.3 in a Qube and it worked I never tried it the other way round

The lack of ram/undetected presence of a simm on one side of a ram bank should also disable the other simm,  it seems like you have 2x8mb & 1x32 =48mb, thus It's odd what you seeing at least from my experience it is.  iirc the Turbo chipset sees both simms in the same bank and one big/wide simm much like  certain Quadras and Power Macs do.

Have you tried swapping the simms about, do you have a Quadra 650/660av or something to try them in?

If I was you, I'd junk this ram you have and get some decent 4x32mb simms of eBay, it can be had for 20 bucks or less for a complete set in most cases brand new.  I got some 70ns Parity FPM branded Silicon Mountain for my Slab and it works fine and passes all ram tests and shows 128mb.

Here is an ebay auction for some FPM memory, but i am not sure if it will work in a color slab.  The description says double sided simms, which it looks like will not fit in the ram slots.

Here is the auction.

http://cgi.ebay.com/4x32MB-72pin-FPM-Simm-HP-Multimedia-IBM-Aptiva-2144_W0QQitemZ280017573439QQihZ018QQcategoryZ3690QQcmdZViewItem

Any Thoughts?

Those look pretty much the same as mine, they are not parity that's for sure which you do have to option of using if you so desire on a NeXT.  They are 60ns which is supposed to give a performance edge, I've never realised this though in the real world.

AFAIK 32mb simms are populated on both sides with chips, I think they have to be for the address space, only small simms like 8mb where done on one side as it was in effect a 16mb unit with the chips missing of one side to make 8mb, hence the reason why most 8mb have solder pads on one side where the chips sould go.

They seem to be used and he makes mention you'd get varying makes, it would probably be better to get 4 matching simms.  When I got mine I paid 20 bucks for 4 brand new simms not 2nd hand, though mine where 70ns parity FPM simms.

Quote from: "nextchef"Here is an ebay auction for some FPM memory, but i am not sure if it will work in a color slab.  The description says double sided simms, which it looks like will not fit in the ram slots.

Here is the auction.

http://cgi.ebay.com/4x32MB-72pin-FPM-Simm-HP-Multimedia-IBM-Aptiva-2144_W0QQitemZ280017573439QQihZ018QQcategoryZ3690QQcmdZViewItem

Any Thoughts?

I've been purchasing 72 pin ram for Turbo's from M.C. Howard Electronics and have been very happy with it.  The memory they supply is new, matched sticks of 60ns, non-parity FPM double-sided ram.  Their auctions run every few days and I usually get 128Mb's for $9.99 USD.  I've tested it in a Mono Turbo Slab as well as a few Turbo Color Stations and it works well.

http://cgi.ebay.com/32-MEG-60NS-72-PIN-SIMMS-FPM-NON-PARITY-4_W0QQitemZ110027683631QQihZ001QQcategoryZ3690QQrdZ1QQcmdZViewItem

http://stores.ebay.com/M-C-Howard-Electronics-Inc

Wow, that's cheap for sure, I might buy some myself and max all my Macs out for that price.

lot of 20 for USD 50.  So how much memory can I put in a color slab.  Can I fill all 8 slots with 32m chips, or am I limited to 128m total

Quote from: "nextchef"lot of 20 for USD 50.  So how much memory can I put in a color slab.  Can I fill all 8 slots with 32m chips, or am I limited to 128m total

If your Slab has 8 memory slots then it's a non-turbo and requires 30 pin ram.  You can add 4Mb sticks x 8 = 32Mb total.  M.C. Howard sells 4Mb 60ns non-parity 30 pin ram for $9.99 USD for 4 sticks, so it would cost you about 20 bucks + shipping to max the ram in your machine if you win the eBay auction(s).

Quote from: "Nitro"

Quote from: "nextchef"lot of 20 for USD 50.  So how much memory can I put in a color slab.  Can I fill all 8 slots with 32m chips, or am I limited to 128m total

If your Slab has 8 memory slots then it's a non-turbo and requires 30 pin ram.  You can add 4Mb sticks x 8 = 32Mb total.  M.C. Howard sells 4Mb 60ns non-parity 30 pin ram for $9.99 USD for 4 sticks, so it would cost you about 20 bucks + shipping to max the ram in your machine if you win the eBay auction(s).

Ok , then I am really confused, since they appear to be 72pin.  The memory slots are different than on my mono motherboard.  They have two sections of pins separated by a space, and I counted the slot and it has 72 pin contacts.  They are white connectors, but two of them have metal retaining clips and the other six are plastic.  It came with two memory modules in it, and they have 72 pins with a 72 printed on the edge.  I will take some pics and see if I can add them to this message.

(http://img319.imageshack.us/my.php?image=ramslotsdq4.jpg) (http://img327.imageshack.us/my.php?image=ramfrontoc9.jpg) (http://img175.imageshack.us/my.php?image=rambackko2.jpg)

My bad, I explained that incorrectly.  Non-turbo NeXTstations can use a maximum of 32Mb of ram, 30 pin ram in the Mono Stations and 72 pin ram in the Color Stations (single-sided).  You'll need 8 sticks of 4Mb 72 pin single-sided memory to max your Slab.

Quote from: "brams"Wow, that's cheap for sure, I might buy some myself and max all my Macs out for that price.

I can't believe the memory for Turbo's is so cheap. :) They combine shipping on multiple auctions too.

Quote from: "Nitro"My bad, I explained that incorrectly.  Non-turbo NeXTstations can use a maximum of 32Mb of ram, 30 pin ram in the Mono Stations and 72 pin ram in the Color Stations (single-sided).  You'll need 8 sticks of 4Mb 72 pin single-sided memory to max your Slab.

Quote from: "brams"Wow, that's cheap for sure, I might buy some myself and max all my Macs out for that price.

I can't believe the memory for Turbo's is so cheap. :) They combine shipping on multiple auctions too.

Damn, that probably means that the auction I bid on is the wrong one.  Anybody want to buy some memory. :)
From his other auctions, it appears that he does not have any 4Mx72 memory.  Here is his store link for anyone that needs it.

http://stores.ebay.com/M-C-Howard-Electronics-Inc

How about this one, will 8 of these work?

http://cgi.ebay.com/4MB-FPM-60NS-1x32-72pin-GENERIC-MEMORY_W0QQitemZ6879421593QQihZ013QQcategoryZ3690QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

Quote from: "nextchef"How about this one, will 8 of these work?

http://cgi.ebay.com/4MB-FPM-60NS-1x32-72pin-GENERIC-MEMORY_W0QQitemZ6879421593QQihZ013QQcategoryZ3690QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

I've used the following company before, but you'll just have to review their return policy and see if it works for you.  That's what I've done in the past.  I've purchased their 8Mb sticks for a few NeXTdimension boards and they worked fine, but for the low price I was willing to toss them on the bench if they didn't work.  Their 4Mb 72 pin FPM non-parity ram is $2.00 USD a stick.

http://www.18004memory.com/browse/cats=2-201/72-pinfpmnon-parity.asp?&guid=04E115DC4B7F4D5C973B29CABD31310F

So then 4M are the largest that can be used because they need to be single sided?  Compuvest on ebay has them for 1.99 USD,but the shipping is $3 higher.

Thanks for the link.

Bumping this thread - actively looking for matched set of 4 x 32MB 72-pin FPM 70ns SIMMs, for 128MB total.  Potentially looking for TWO sets.

Hunting on eBay doesn't find much, maybe MemoryMasters listings, but they are for 60ns and I worry they end up detected as 100ns?

Or if anyone has sets they'd like to sell, i'm all ears.

Stumbled on two NeXTStation Turbo Colors in various states, and slowly bringing them up to snuff!

I've used these 70ns SIMMs from Memory Masters and they work well.

https://www.ebay.com/itm/155770919471

Quote from: Nitro on June 23, 2025, 12:08:59 PMI've used these 70ns SIMMs from Memory Masters and they work well.

https://www.ebay.com/itm/155770919471

I was looking at these sets (for a bit less), same seller.  Can't tell if they'd work or not?

https://www.ebay.com/itm/175589529913 <-- Double Sided?
https://www.ebay.com/itm/155379355884

Quote from: luVWagn on June 23, 2025, 12:29:26 PMI was looking at these sets (for a bit less), same seller.  Can't tell if they'd work or not?

https://www.ebay.com/itm/175589529913 <-- Double Sided?
https://www.ebay.com/itm/155379355884

Memory Masters tech support on eBay recommended the second listing.

Enroute, will report back

Second set worked a treat in my slab.