The MP project

Been wanting to build a dual MP mac for some time but 9600's have been hard to come by, even offered $40 for one!
However, this week i rescued from a dumpster a umax 900. The thing was a grimy mess and was full of evil smelling dustballs. Took the whole thing apart and cleaned it thoroughly using toothpaste and an toothbrush on the plastic and prosolve/armour all spray. Some pieces were too bad to save but managed to get the video card, the apollo card and the motherboard and power supply and the plastic innards.

Luckily i had a s700 case that had a logic board but no innards but was clean and had a scsi cd.

Pulled a 604e 200mhz cpu from the 8600, added some ram, the video card, a couple scsi drives, etc, found the umax cd that came with the 700 and booted up. Installed ok and run pretty good with the 600+ mb of ram. One set is mismatched and the unit only reboots if you reset the cuda. Will swap later. Tested a second 604e 200mhz and it is fine.

Need to pull a 10/100 ethernet card from the 7600. The 128 turbo video card eems to run good, need to test against the ati rage cards, although it may depend more if i want to try linux on it.

Found a 9.1 and a 4.5 gig scsi drives. The cd is a bit flaky, so it needs replacing too.

Now we know the parts are all working time to take everything apart and rebuild using the 900 logic board and the 2 604e cpu's and fix the ram. May have to think about additional cooling as 604's run very hot and the 700 is a desktop case.

Then we need to think about the OS. The offical umax ver 8 runs ok but some quick research shows upgrading to 9.x or osx is problematic and the umax ftp site has disappeared again so no updated files...

Besides classic os does not use mp - although it allows applications like photoshop to use both cpu's. Maybe it's time to see how well it would run linux...but which one?

Finished the project as far as it could go without a dual cpu. Added the 2nd case fan and a 10gig scsi drive and installed OS 8.0 from the original UMAX CD plus some stuff from the original UMAX applications CD. After the usual extensions tweaking it runs really well, quite snappy. Pretty quiet too considering the amount of cooling. Put the extra parts (2nd floppy, 700 motherboard...) in a box in the closet. Have to put this project away until the term is over...

will post pics later


Everything was looking good but one hitch - the 2nd cpu slot is about 1" from the first and the standard heat sink on a 604 card is about 1" so there is no room for 2 cpus!

Either need to find slimmer 1/2" heat sinks...601 cards? or trim off the excess metal. Added a 2nd 5" case fan but with the heat given out by a 604 i don't want to risk running it without heat sinks on the cpu. Could also take off the existing sinks and try and retrofit some sinks taken from 601's or from pc's. Anyone have solved this problem??

Hokusai's picture

Just to comment, I think the S900's second CPU slot required a special type of card. I don't think you can just plop any 'ole card in there. I don't know if this was because of space concerns (such as you are seeing) or a hardware reason.

dankephoto's picture

Yeah, AFAIK this is true. They've got a multipin header on the top edge that takes some kind of cable connecting the two CPUs. I've got a few of those CPUs laying about somewhere around here. However I've never had the actual MP box for which they were designed . They do work as a single in 'normal' PCI Macs though.

dan k

That's interesting - where does the cable go? The second cpu must be different than the normal 604's i've tried. The slot looks exactly the same but the electronics must be different.

To reduce the size of the heat sink i'll take it off as soon as i find the right size of hex and replace it with one taken from a logic board, possibly a 601 or 603 heat sink.

Would be interested in one of these cards for the second cpu.

cheers - gord

dankephoto's picture

IIRC the cable jumps between the CPUs, so you need two CPUs of the proper type, as well as the cable.

dan k

check e-Bay. Macintosh componets, cpu's there is someone selling a set of CPU's out of a S900D. Check it out

dankephoto's picture

I thought for sure I had the Umax service docs, but I can't seem to find them. I did grab this quote from the S910 User Guide:

Installing a Second Processor Card
The SuperMac S910 includes a second central processing unit (CPU)
slot. To further increase the performance of your computer, you can
install the Advanced Scalable Processor Design (ASPD) card in the
CPU slot.

dan k

Don't use ebay anymore, was ripped off 3 times and ebay doesn't help so your only recourse is to leave bad feedback - and to make matters worse the seller who ripped me off put bad feedback on me!

I buy now off, a really good bunch (but in Canada)

found my manual and you do need a ASPD card....

maybe someday

Hokusai's picture

I know that you probably aren't paying attention to this topic anymore, but I got this picture of the dual processors from an auction on eBay.

Thanks for the picture!

I finally got a 604e MP cpu this month for xmas. Can't post any more pics here for some reason so i've set up a FLICKR account where i can post. Have to dig out all the project photos and organize them.

The card is a 180 mhz MP and i have a 8500 MP box to try in out in. I took a photo comparing the backside of the MP card with a regular 604e for comparison.