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Wallstreet PDQ CPU swap

MacUp72

Well-known member
are the CPU/ RAM daugtherboards from the same family actually swappable? eg the 266Mhz board from a 14" PDQ to a 12" 233Mhz PDQ , both late 89?
 

Unknown_K

Well-known member
Not sure. The original release motherboards could do 83Mhz FSB (292 Mhz being the high end) while the second revision would only do 66mhz FSB (300Mhz being the high end). You also need PC100 RAM for 83FSB while later ones did fine with PC66.

Because of FSB and cache speed the 292 was faster then the 300.
 

MacUp72

Well-known member
to my knowledge all PDQ have 66 Mhz bus speed (233, 266,300Mhz) also the last revision the PDQ LE ( 12") that I have now..even the Lombard have 66 Mhz. Only the Pismos have 100 Mhz.The daughterboard connectors are different later I guess..
 

avadondragon

Well-known member
to my knowledge all PDQ have 66 Mhz bus speed (233, 266,300Mhz) also the last revision the PDQ LE ( 12") that I have now..even the Lombard have 66 Mhz. Only the Pismos have 100 Mhz.The daughterboard connectors are different later I guess..
That is correct. From what I recall reading there were some stability related issues with the higher FSB models of the WS (possibly due to heat) which is why they backed it down to 66Mhz on the later models.
 

MacUp72

Well-known member
Not sure. The original release motherboards could do 83Mhz FSB (292 Mhz being the high end) while the second revision would only do 66mhz FSB (300Mhz being the high end). You also need PC100 RAM for 83FSB while later ones did fine with PC66.

Because of FSB and cache speed the 292 was faster then the 300.


these are not the PDQ, these are the first Wallstreet series.

btw, is here somewhere a tutorial for PostFactorOSX? Tomorrow I'll try to install Tiger ( if the 512MB RAM arrive and work :LOL:)
 

Byrd

Well-known member
Not sure. The original release motherboards could do 83Mhz FSB (292 Mhz being the high end) while the second revision would only do 66mhz FSB (300Mhz being the high end). You also need PC100 RAM for 83FSB while later ones did fine with PC66.

Because of FSB and cache speed the 292 was faster then the 300.

Yes but I thought with the "Grackle" bus controller on the CPU daughtercard itself, the WS/PDQ motherboard didn't care what FSB it was.
 

MacUp72

Well-known member
Yes but I thought with the "Grackle" bus controller on the CPU daughtercard itself, the WS/PDQ motherboard didn't care what FSB it was.
ah, now I get what you mean, interesting, I thought the FSB controller is on the motherboard..
but in practice the daughterboard connectors ( and other ICs ) are the difference I guess.
So most probably only the most similar PDQ revision is swapable..I consider getting a second ( beat up) PDQ, then I will know..
:LOL:
 

avadondragon

Well-known member
The FSB speed and clock multipliers are set by resistors on the daughterboard and it is possible to change those settings to say overclock the board or swap out the processor for a G4. You would also need to swap out the cache chips to match your new processor speed. I've moved CPU cards between different models of PDQ with no problem.

I don't know if there's anything fundamentally different about the LE but it won't hurt to try.
 
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MacUp72

Well-known member
ok, today came a cheap, beat up 14" PDQ with original power adapter, install OS 8.5 CD and a 266Mhz 1MB L2 CPU and I swapped it, works without any problem.
(y)
 
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Trash80toHP_Mini

NIGHT STALKER
I haven't looked into it, but mine seems to think it's a PDQuicker. The processor is reported as running at the Lombard's 333MHz clock.
 

Trash80toHP_Mini

NIGHT STALKER
I picked up a tricked out Pismo and the PDQ from their very resourceful, knowledgeable first owner on craigslist. I imagine he overclocked its 300MHz CPU by 11% which isn't all that much really.
 

MacUp72

Well-known member
I'd really like to see a resoldered CPU daughterboard from one of these PDQs..
the Lombard already look different and the later Pismos even more of course.

l.jpg



The only page about that mods is in french here:

Bildschirmfoto 2023-02-05 um 09.01.24.jpg



avadondragon:
The FSB speed and clock multipliers are set by resistors on the daughterboard and it is possible to change those settings to say overclock the board or swap out the processor for a G4. You would also need to swap out the cache chips to match your new processor speed..

well, that would be another thing..never done that, if that's really worth it, hm..
 
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Trash80toHP_Mini

NIGHT STALKER
Multiplier resistors shouldn't be all that difficult and an 11% bump shouldn't take the cache components out of spec I'd think. Of course that assumes you're starting point would be the high end 300MHz CPU card.

Are connectors for the CPU card available? We've an in depth thread about G3 upgrade for the Blackbirds. IIRC ther are CPUs with on board cache in excess of the OEM cards and clock multipliers that would be suitable for new build. I've been musing about doing a board for the 1400c and the PDQ ought to be similar wnough, especially so without the need for L2.

Given connector availability or ability to harvest them from donor cards, G4 might be within the realm of possibility?
 
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