How to tell a Turbo slab from a non-Turbo...

by looking at the motherboard or any other hints other than CPU speed ??

Thanks in advance guys

easiest way w/o powering on is if the cpu is removable and not builtin.

I have seen, and very recently, a color 25mhz board that looked exactly the same as a 33mhz color board except the cpu was builtin. Normally you will find the placement of the video chip and the rom socket in different locations on a turbo and non-turbo, and the amount of ram slots would differ. But I saw a non-turbo color whos mobo is different than any other 25mhz color I had seen. So, if you asked this a few weeks ago, I would have given you a dozen different ways to ID a board. But now, I think safest bet is turbo=socketed/removable cpu, non-turbo=builtin/non-removable cpu.

I see... Thanks for the heads up Multi.

I originally thought of looking the crystals, but I'm not 100% sure what the non-Turbos have. The Turbos seem to have a 100Mhz main crystal, so I guess it's divided by 3 to get 33.3...Mhz

Any other ideas anyone?

Quote from: "da9000"
Any other ideas anyone?

On 25 MHz machines the heatsink doesn't cover the whole CPU, on 33MHz it does cover.

First a Turbomachine:



second the same motherboard with a 25MHz CPU:

Thanks for the pics Andreas.

I also noticed that certain components vary (that DC-DC "thing" near the PSU), and also the 040 is a bit under the floppy drive on the non-Turbos. The crystal remains at 100Mhz on both.

There are also non-Turbos (25Mhz) but with the Turbo chipset (33Mhz capable?). How do you recognize those? From the 4 RAM slots or some other way?

Thanks

Quote from: "da9000"There are also non-Turbos (25Mhz) but with the Turbo chipset (33Mhz capable?). How do you recognize those? From the 4 RAM slots or some other way?

Thanks

Ill take a pic of the color 25MHz I have which matches a turbo exactly except for the cpu being 25mhz and builtin.  The pics posted earlier are of the normal mobos, this 25mhz I have is unique, never have seen another like it.

Quote from: "multi"

Quote from: "da9000"There are also non-Turbos (25Mhz) but with the Turbo chipset (33Mhz capable?). How do you recognize those? From the 4 RAM slots or some other way?

Thanks

Ill take a pic of the color 25MHz I have which matches a turbo exactly except for the cpu being 25mhz and builtin.  The pics posted earlier are of the normal mobos, this 25mhz I have is unique, never have seen another like it.

Duh, I didnt notice that Andreas had posted a pic of one with a 25mhz cpu. So, there you have it. That's easiest way to tell(by looking at the cpu, builtin or not).

I'm confused. If there is such a thing as a non-Turbo (25Mhz CPU) with a Turbo chipset, then the CPU would look exactly like a non-Turbo (25Mhz CPU), yet some other pieces would be different, no?

In other words, I believe there are 2 25Mhz systems:

1) 25Mhz CPU, 25Mhz chipset
2) 25Mhz CPU, 33Mhz (capable) chipset

Seeing how they both have a 25Mhz CPU, wouldn't both CPUs have the smaller heatsink? That's the understanding I got from Andreas' photos.

Quote from: "da9000"I'm confused. If there is such a thing as a non-Turbo (25Mhz CPU) with a Turbo chipset, then the CPU would look exactly like a non-Turbo (25Mhz CPU), yet some other pieces would be different, no?

In other words, I believe there are 2 25Mhz systems:

1) 25Mhz CPU, 25Mhz chipset
2) 25Mhz CPU, 33Mhz (capable) chipset

Seeing how they both have a 25Mhz CPU, wouldn't both CPUs have the smaller heatsink? That's the understanding I got from Andreas' photos.

The pic Andreas posted and the color station I have have what looks exactly like a turbo mobo, except with a builtin 25MHz cpu. If you notice in the second pic the cpu is builtin and has a small heatsink.

As for any other pieces being different on the mobo, I didnt find any. I was comparing to a turbo color board and only diff. I saw were the cpus. Everything else on the board was in same exact location was you see on a turbo color(the 4 ram slots, the placement of the ROM chip, the video chip, etc. etc.). Spitting image of a turbo color mobo except for the cpu. Also, it has a fairly recent rom installed.

Hmmm.. I noticed the big "ground" metal bar that goes from one side of the motherboard to the other, isn't present in the Turbo ones. Perhaps that's another indicator for the Turbo chipset vs the non-Turbo chipset...

To corroborate stories of Turbo-chipsetted 25MHz colorstations, I have one sitting right here on my desk, currently down due to a dead disk and its sound box being stolen to revive my cube, but otherwise alive. Also, I found a photo of the same type of motherboard being listed as part of someone else's workstation collection.

As for whether these are actually any different speedwise, I'll say that subjectively my 25MHz colorstation feels faster than my ND Cube (which uses 30-pin RAM), but slower than my Turbo Color slab.

I guess I should have looked more closely at the NeXT FAQ. I quote what it says in there, with some cleanup/additions/clarifications by me (indicated by []):

QuoteNeXT manufacturing introduced the new 25 MHz NeXTstation CPU board [Turbo chipset] into production in late June 19992. [To verify if you have a Turbo or non-Turbo chipset motherboard, you can look to see] which SIMM type your machine uses, by checking the system's memory configuration. You can do this by using the ROM monitor's print memory configuration command m. [...] Turbo-designed boards [Turbo chipset] including the new 25 MHz NeXTstations and all Turbo systems will return messages reporting the memory configuration contained in four sockets (sockets 0-3); old 25 MHz boards [non-Turbo chipset] will return messages for more than four sockets [(sockets 0-7 for all but the 030 cube motherboards, which have 16 sockets I believe)].

Couple of additions for the non-Turbo NeXTstations:

*You can only use 32MB of RAM
*You can only use (256KB?), 1MB and 4MB SIMMs
*They seem to have only one clock setting for RAM: 100ns. Even if 60 or 70 or 80ns RAM is used, they still use a 100ns clock

Edit by Admin: Hotlinked photo removed