SE/30 Socket Upgrade

[aplmak]

I've searched threads but still unclear if it is possible..I bought a MC68030RC33B processor chip. I have a SE/30 logic board with a socketed processor and I am going to try swapping the 16mhz. with this 33mhz.. From what I can tell this is the 33mhz. model without the coprocessor which I don't need because it is already soldered on the board in another area.. basically same configuration as the 16mhz. version. The clock crystal says 33mhz.. so I don't know if I need something higher to match or if the 33mhz. is sufficient.. I understand the bus speed is 16mhz… Anyone know if this might give me any sort of performance enhancement??? I also will be putting a IIsi ROM to make it 32bit clean… 

Thanks Matt

 

[Byrd]

Won't do a thing - the 33Mhz CPU will continue to run at 16Mhz.  If you trawl through the forums you'll see some people have hacked their SE/30 mobos to run at slightly higher speeds, but with caveats.  Best bet would be to look out for an SE/30 compatible '030 or '040 Daystar accelerator for the PDS slot, or a Diimomac '030, or Daystar card that plugs into the '030 socket itself.

 

[Trash80toHP_Mini]

You might also want to check around for the Clock Chipping info on other '030 Systems. If a Mac has problems related to the speed of the processor and is package compatible your faster part might be put to good use.

Byrd, might a slower PowerCache accelerator be shipped to a higher speed with a proc-swap? I've got one for that runs at the same 16MHz clock as its (MacII?) probable host.

Dunno, there are several variables for such an odd duck as that card, just thought I'd toss that notion on the waters..

 

[Elfen]

There's a main crystal of 31 MHz on the SE/30 board. It gives the processors and other chips to run and 1/2 its speed or about 16MHz. It is this half speed which much of the SE/30 processing circuits uses. To get your SE/30 to run at 33MHZ, you need to replace that crystal with a 66MHz crystal. Like wise if you want to run your SE/30 at 25 or 20 MHz, you need to run a crystal a double that speed- 50 or 40 MHz respectfully.

Or so goes the theory. In this case the theory is correct if this were a "Perfect World."

But the other chips on the mother board does not run at anything faster than 16MHz. And the video is synchronized at 16MHz - change that and you lose the video. The same with the other I/O (Serial, ADB, SCSi, etc). And on top of that you need to get faster RAM to run at the higher speed.

So even if you can get your SE/30's 68030 CPU and 68882 MPU to run at a faster speed, you loose everything else.

If you want a faster SE/30, you need to get an accelerator to put on it's PDS Slot. Only then can you run at a higher speed by having a "separate Mac" inside the SE/30 and run all your software for the SE/30's 68030, and then give that processed information back to the SE/30's 68030 so it can display on the video, print it to the printer and save it on the floppy/SCSI hard drive.

There are many accelerators for the SE/30, which one you want to need to research and go ind it.

 

[techknight]

another idea which I dont know if it would work or not, is isolate the clock line to the microprocessor and interface it with an ICS511 clock multiplier. this will double your clock without affecting the rest of the system. Your still bottlenecked by the bus regardless. 

This doubling shouldnt affect asynchronous bus transfers because everything is handled by wait states and DTACK. But the synchronous bus may have problems. I dont know. 

 

[Paralel]

You don't need to necessarily use the PDS slot. One of the significant benefits of a socketed board is using a socketed upgrade in place of the original processor in the socket so that way you don't have to use your PDS slot. They are not easy to find, but they're out there.

 

[olePigeon]

That's what he has, but I think what TechKnight is saying is that you can't just drop a faster CPU in.  Well, you could, but it wouldn't be any faster.  The new CPU would just be downclocked to whatever the crystal is set to.  If you change the crystal so you have a faster CPU, the other components that are dependent on that original crystal operating at its original frequency will fail.

So to avoid that, you only change the line that's in charge of the CPU speed, and put a doohickey in so you can change the frequency without changing everything else.

 

[Elfen]

You don't need to necessarily use the PDS slot. One of the significant benefits of a socketed board is using a socketed upgrade in place of the original processor in the socket so that way you don't have to use your PDS slot. They are not easy to find, but they're out there.

There are several such accelerators for the IIcx as it does not have a PDS Slot, but the CPU & MPU must be socketed. Thing is, would they fit a SE/30, or can you rig up a cable to run from the socket to the add-on board and put that add-on board else where, like next to or on top of the hard drive?

 

[Paralel]

That's what he has, but I think what TechKnight is saying is that you can't just drop a faster CPU in.  Well, you could, but it wouldn't be any faster.  The new CPU would just be downclocked to whatever the crystal is set to.  If you change the crystal so you have a faster CPU, the other components that are dependent on that original crystal operating at its original frequency will fail.

So to avoid that, you only change the line that's in charge of the CPU speed, and put a doohickey in so you can change the frequency without changing everything else.

I should have made what I meant by upgrade more clear, I meant a comprehensive commercial solution like the ones sold by MicroMac, etc... not just a faster processor in the socket

 

[JDW]

You don't need to necessarily use the PDS slot. One of the significant benefits of a socketed board is using a socketed upgrade in place of the original processor in the socket so that way you don't have to use your PDS slot. They are not easy to find, but they're out there.

They are out there indeed:

https://www.flickr.com/search/?q=socket+Daystar&m=tags&ss=0&ct=0&mt=all&w=66071596%40N00&adv=1

 

[Trash80toHP_Mini]

. . . can you rig up a cable to run from the socket to the add-on board and put that add-on board else where, like next to or on top of the hard drive?

Short answer: no

Long answer: even at 16MHz, high speed signalling would be problematic. There's a thread over on 'fritter about my quest to hack a 1400/G3 Accelerator into a Duo. Dr. Bob's running commentary in the back and forth amounts to an excellent tutorial on the subject.

 

[massiverobot]

I've searched threads but still unclear if it is possible..I bought a MC68030RC33B processor chip. I have a SE/30 logic board with a socketed processor and I am going to try swapping the 16mhz. with this 33mhz.. From what I can tell this is the 33mhz. model without the coprocessor which I don't need because it is already soldered on the board in another area.. basically same configuration as the 16mhz. version. The clock crystal says 33mhz.. so I don't know if I need something higher to match or if the 33mhz. is sufficient.. I understand the bus speed is 16mhz… Anyone know if this might give me any sort of performance enhancement??? I also will be putting a IIsi ROM to make it 32bit clean… 

Thanks Matt

I have this in my se/30:

http://www.micromac.com/products/diimo_030.html

and it works great.

Their webpage is up, and they have an order form- are they really still in business?

 

[cb88]

No they are not in bussiness... you can't even find a card on ebay these days (I haven't seen one in months).... of course a few turn up once in a blue moon sometimes they go cheap sometimes people go crazy and spend way too much on them....

 

[JDW]

Micromac has been out of business for many years, which makes me wonder who maintains their defunct website. The text description of the DiiMO PDS accelerator on the Micromac site is accurate, but the product photo shown is NOT of the SE/30 edition. You can see the SE/30 edition card with floppies and original box in my Flickr collection here:

https://www.flickr.com/search/?w=66071596@N00&q=diimo

As mentioned in the text description under my Flickr card photo, I bought it new-in-the-box from NEXTRO here in Japan some years ago. It appears they sold through their inventory a while back and no longer offer it. Too bad, because it' so great card. I like my 40MHz DAYSTAR too, but the DiiMO's 030 is more software compatible.

 

[Paralel]

As JDW has mentioned, NEXTRO is an excellent company for old Mac parts. They have no trouble working with people here in the states. I bought a PB550c processor daughtercard from them and the were very professional, responsive, and items are exactly as described.