quadra 800 in 700, PSU concerns

[broccoliwithattitude]

hello,

sorry if the question have been already asked, but i would like to put a quadra 800 motherboard into my quadra 700 case.
both work, but for a project i am doing i needed the max 136mb ram, which my quadra 700 did not have.

so i got a cheap 800, i hate the case (that also came quite bashed) and since they both have a wombat form factor, the 800 just fits.

however the psu of the 800 does not fit and i wanted to drop in just the 700 psu, but when i did with another 800
that died, the transformer of the 700 psu burnt and i had to get a new one. the mobo might have been already dead but not sure if the cause of the 700psu failure was the 800 or the fact that it was just old.

so for the outputs:

quadra 800 psu:

+5: 30A max
-12: 0.75A
≠12: 5A max
≠5 trkl: 0.1A

quadra 700 psu:

+5V:1mA continuous
-12: 1.0A
+12: 1.5A
+5V: 12A

my main concern is the 5V rail, since the 700 psu has max 12A, and with max ram it needs to feed a lot, maybe more than 12A. i won’t use the cd-drive so that’s less and also i have a scsi2sd which lowers the 12 rail but.

does anyone have a suggestion? should i just get an adapter and use a new psu? if so, which one would you suggest?

sorry for the disturbance

thanks!

 

[volvo242gt]

Use a power supply from a IIvx, Centris 650, Quadra 650, etc. Has more amperage than the stock IIci power supply used in the 700 case, but fits in it perfectly.

 

[AlpineRaven]

I am using Q800 in Q700 case with Q700 PSU - no issues at all, also have Nubus and DOS Compatible card in it too.
Currently has 64mb RAM and full VRAM, wide SCSI etc.
Cheers
AP

 

[lobust]

I am using Q800 in Q700 case with Q700 PSU - no issues at all, also have Nubus and DOS Compatible card in it too.
Currently has 64mb RAM and full VRAM, wide SCSI etc.
Cheers
AP

+1 here and no problems with it.

Q800 psu has to support up to three drives and three expansion cards.

Q700 maxes out at one drive and two expansion cards.

 

[broccoliwithattitude]

I am using Q800 in Q700 case with Q700 PSU - no issues at all, also have Nubus and DOS Compatible card in it too.
Currently has 64mb RAM and full VRAM, wide SCSI etc.
Cheers
AP

+1 here and no problems with it.

Q800 psu has to support up to three drives and three expansion cards.

Q700 maxes out at one drive and two expansion cards.

thank you!

the first time i put my q700 psu on a q800 board the transformer burnt down and the q800 did not boot at all, but maybe that quadra was defective to begin with.

this other one is confirmed working (works with its own psu in its case), so i wanted to ask before attempting again (i got another q700 psu).

i have a nubus sound card, scsi2sd, ppc upgrade card and floppy. so i guess the q700 psu will be alright! i'm going to add 136m of ram for an app i am making but i guess it can work.

i also hunted down a 1U server psu to put in place but to desolder all the cables + the resistor trickle hack was kind of scaring me..

Use a power supply from a IIvx, Centris 650, Quadra 650, etc. Has more amperage than the stock IIci power supply used in the 700 case, but fits in it perfectly.

i thought of doing that but had no luck finding a spare one...

 

[lobust]

thank you!

the first time i put my q700 psu on a q800 board the transformer burnt down and the q800 did not boot at all, but maybe that quadra was defective to begin with.

this other one is confirmed working (works with its own psu in its case), so i wanted to ask before attempting again (i got another q700 psu).

i have a nubus sound card, scsi2sd, ppc upgrade card and floppy. so i guess the q700 psu will be alright! i'm going to add 136m of ram for an app i am making but i guess it can work.

i also hunted down a 1U server psu to put in place but to desolder all the cables + the resistor trickle hack was kind of scaring me..

i thought of doing that but had no luck finding a spare one...

I tried the ppc upgrade card in mine, and it did work, but beware that it gets very hot in that little case - it's bad enough on a stock 700, but the higher clock of the wombat board and the confined space it's in are a bad combo...

 

[broccoliwithattitude]

I tried the ppc upgrade card in mine, and it did work, but beware that it gets very hot in that little case - it's bad enough on a stock 700, but the higher clock of the wombat board and the confined space it's in are a bad combo...

i used that ppc with my quadra and i don't remember getting too hot, although i was doing light stuff. what i'm working on has heavy math calculations so will make the cpu hot... maybe i should zip tie a fan on the ppc upgrade card....

 

[lobust]

I don't remember what I was doing at the time, but I had the PPC card installed and I had a Supermac Thunder II GX in the upper slot.

I started getting video artifacts and shut it down. I took the cover off and found that the video card was getting cooked from the heat coming off the 601.

It didn't cause any damage and everything was fine after it cooled down, but I pulled the PPC card out of that system after that.

The 601 kicks off quite a bit more heat at 33/66Mhz than it does at 25/50 in the stock 700...

 

[broccoliwithattitude]

I don't remember what I was doing at the time, but I had the PPC card installed and I had a Supermac Thunder II GX in the upper slot.

I started getting video artifacts and shut it down. I took the cover off and found that the video card was getting cooked from the heat coming off the 601.

It didn't cause any damage and everything was fine after it cooled down, but I pulled the PPC card out of that system after that.

The 601 kicks off quite a bit more heat at 33/66Mhz than it does at 25/50 in the stock 700...

ugh then probably will be an oven with ppc, i don't want to fry my audio card.
maybe a fan would help but there is not much air intake i guess.. i read of people putting a zip-tie fan on the ppc upgrade card but not sure it will help much, maybe i should focus on another ppc system that won't become a crock-pot when working...

 

[CuriosTiger]

My 601 card runs at 66MHz, and I am not having heat problems. I have it installed in a Q650, but I'd think that it'd give off similar heat regardless?


That said, I can feel radiant heat off the heat sink, and I imagine that if I populated the ADJACENT NuBus slot, that might be a problem.

 

[lobust]

ugh then probably will be an oven with ppc, i don't want to fry my audio card.
maybe a fan would help but there is not much air intake i guess.. i read of people putting a zip-tie fan on the ppc upgrade card but not sure it will help much, maybe i should focus on another ppc system that won't become a crock-pot when working...

A fan would go a long way just to get some air circulating around it.

My 601 card runs at 66MHz, and I am not having heat problems. I have it installed in a Q650, but I'd think that it'd give off similar heat regardless?


That said, I can feel radiant heat off the heat sink, and I imagine that if I populated the ADJACENT NuBus slot, that might be a problem.

650 case is much better for dissipating heat away from the cards compared to any of the towers by simple virtue of the cards being vertical. But also the lid is much better ventilated, and there is more air gap above the cards compared to the 700.

But the 700 is just so visually appealing

 

[volvo242gt]

If the 700 wasn't crippled with only two Nubus slots, it probably would work better with the PowerPC upgrade cards, when another card is installed, heat-wise.

 

[CuriosTiger]

A fan would go a long way just to get some air circulating around it.



650 case is much better for dissipating heat away from the cards compared to any of the towers by simple virtue of the cards being vertical. But also the lid is much better ventilated, and there is more air gap above the cards compared to the 700.

But the 700 is just so visually appealing

I have a Quadra 700 as well, although mine is slightly bizarro because one of the NuBus slots was apparently mounted backwards. Mine came from an Apple Authorized Reseller that I used to work for.

Come to think of it, the bizarro NuBus slot may be why they never sold it.

But it works fine, I just have to accept that I have a one-slot Quadra 700. That one slot has a PrecisionColor/24 video card in it, and the PDS slot is consequently inaccessible.

(Yes, I could desolder the NuBus connector and flip it around. But I'm not going to risk board damage to do that.)