Home build NeXT Accelerator

Please ba aware that a lot of the below content is snips of stuff and other relavent material. It's 3AM and I really can't be assed to compile all of this into a formal writeup.
Sdinet mentioned this to me however short of sending me a few pictures and telling me he still knows the creator, that's all we really know.
Apparently, it's rather similar to a modification that is commonly applied to Quadra macs. I was pointed to here (http://www.applefritter.com/node/20510) and here (https://web.archive.org/web/20081227223917/http://homepage.mac.com/schrier/q605.html).

sdinet also told me that...

Quotethe previous owner said he replaced the PPL doubler on the motherboard with a 100mhz version...  Or he said add a doubler as a small surface mount board then supply a heatsink for the stock PPL.

It's also apparent that the 25Mhz cpu was desoldered and replaced with a 33Mhz 040.

I was also given several photos of the finished product.







I'll try and get more info and clean this post up but it's certainly a start.

very interesting, but is this only for slabs? or is this a cube?

Thanks

From what I was told this was done in a color slab. I don't know how exactly if at all it differs from the design of the 040 Cube or the mono slab minboard.

Quote from: "pentium"It's 3AM .

go to bed now!

:lol:

It looks similar to the 50MHz Color Slab that gborgns made.

http://www.nextcomputers.org/forums/index.php?topic=56

Quote from: "Nitro"It looks similar to the 50MHz Color Slab that gborgns made.

http://www.nextcomputers.org/forums/viewtopic.php?t=56

Well I'll be damned. That's it alright.
Oh, it looks like he revised it recently too. I must of missed it.  :P

Yes, that is my handy work.

It is a one-off proof of concept, to demonstrate that the original prototype using parts from a Sonnet Quaddoubler, could be repeated on another system.

I am in the process of reducing some of my computer collection.  So I finally decided to sell it.

A couple of clarifications:
The 25MHz processor was replaced with a 40MHz 68040.
The on motherboard 70MHz PLL was replaced with a 100MHz PLL.

I am not interested in producing the mod for sale.  It is too labor intensive.  There should be enough information in my revised post: http://www.nextcomputers.org/forums/viewtopic.php?t=56 to complete the mod.

I can post more info on how to make the custom doubler board shown, if there is any interest.

can this be done on a 040 cube?

The Turbo (33MHz) Cube uses a similar chip set.  So it maybe possible.  However, I have not attempted the mod.

hey GUYS!!!  Yes this is gborgns handy work!  He graciously sold it to me, and I am EXTREMELY and FOREVER grateful!!!

I am ordering parts as we speak to modify a turbo color slab using his same schematics (Circuit board and the 88916). I will post my progress, and if I can get the onboard 70mhz  PPL to overclock to 100Mhz, then this might be a fairly easy mod to recreate!

Will keep all posted as I progress =)

gborgns, I noticed 2 of the pins on the backside of the 040 CPU are connected, any reason why, do I need to do this if I overclock a 040 33mhz cpu on a turbo color?

I love the comments about attempting the overclock on a Cube board, I would be willing to try it on a 25Mhz cube, but TOO Terrified to try it on my 33MHz cube.

is this a 040 40mhz that would work for the MOD on a socketed next board?

http://cgi.ebay.com/Weitek-IC-40MHz-8601-040-GCD_W0QQitemZ260325964664QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3c9ca2fb78&_trksid=p3286.m20.l1116

Weitek? Wat?
Either Motorola let Weitek make clone 040 chips or that is not a 68040 processor and I'm going for the latter.

The resistor connecting the two 68040 pins on the bottom of the board was actually there before I performed the mod.  I looked into it and believe it was used to disable the bus grant function.   But it's been a while.

I don't think the mod would work on a 25MHz cube.  I'm pretty sure that the chip set is different.  

The 33MHz Turbo cube has the same chip set as the Turbo slab.  So the mod should work, however, there may be bus issues when trying to use it with a dimension board.

so just got a Turbo Color to use for this project, now the real fun begins!  Will keep everyone posted on my progress.

anyone an expert at schematics?  

I am trying to order the SMD resistors and capacitors for the clock doubler board...

But am having some troubles, for example when I order the SMD 10uf capacitor, there are varying voltages (6v-25v) and variances (10%, 20%, -20 to 80%), does it matter which one I choose, or is the only criteria that matters 10uf?

I am looking at ordering them from http://www.arrownac.com/

If someone could read the schematics and cross reference the part numbers at arrow's website and generate a parts list for me to order based of the schematic for the doubler I would be very grateful!  (I already have the circuit board and PPLs)

I can't answer your question, but adding a suggestion.. have you looked at using Digikey? They seem pretty awesome. several people I know like using them.

Hello: Did anyone ever write a software drive accelerator for NeXT like Conectix Speed Doubler for Mac , also Nick I don't now if this would help tinkering with cloc speeds or could be adapted http://www.micromac.com/products/speedy.html , what about Frankensteining  this http://homepage.mac.com/schrier/q605ppc.html a 68040 to PPC upgrade, socketed or hooked up to the cube bus , drivers need ??? Will ram doublers or socketed conversion 30 pin to 72 pin work  on any NeXT's , What happens beyond 128Mb of Ram that causes incompatability and can the problems be upgraded?  I'm willing to try some of these ideas and post here, wouldn't it be cool to hotrod these, I have a pyro but I'm talking going way beyond with a PPC  upgrade  just need to locate the old products cheaply! Best regards Rob Blessin  Also is there a way to boot Rhapsody on Black Hardware by creating a hybrid OS?  8)