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Quadra 700 issue
Posted by: marmotta on 2015-10-28 04:29:34
Sorry fo my poor english...

I have buy used Quadra 700, first times I powered up it not immediately switch on but... after some minutes! And with power button I not able to power off, if i push the switch the mac only reset... And now after some test and cleaning of the pcb it never switch on. I able to switch on only with a bridge pin 9 and 10 of psu or if I plug the psu in the motherboard with power cable plugged.

But I have another problem... this is a screenshot of my screen (without hdd), recap solve all my problems? What caps i need to change?
Posted by: olePigeon on 2015-10-28 09:16:21
A recap is pretty much need for the Quadra 700.  Surprisingly, there isn't a Quadra 700 tutorial on the Wiki.

I'm sure Uniserver knows which caps need replacing.
Posted by: marmotta on 2015-10-28 11:20:51
Uniserver help me!  🙂

Quadra 700 have only 3 types of caps, and all small and yellow

I order a set of tantalum 16v 10uF and 16V 22uF? ... other capacitor is too small to read capacity.
Posted by: 360alaska on 2015-10-28 11:33:29
Quadra 700 has all solid state caps on the LB and should not need recap. in the case of this guy I would tell you to make sure your pram battery has not exploded and if that's ok look into recapping the power supply...
Posted by: marmotta on 2015-10-28 13:16:28
Quadra 700 has all solid state caps on the LB and should not need recap. in the case of this guy I would tell you to make sure your pram battery has not exploded and if that's ok look into recapping the power supply...
Sure? I know tantalum capacitors not have a unlimited life... Battery is new and the old not have lose acid, the psu seems to work good, voltages are stable and in tolerance
Posted by: TheWhiteFalcon on 2015-10-28 13:37:31
Check the VRAM.
Posted by: marmotta on 2015-10-28 13:55:31
Check the VRAM.
Could be, but: how can I do? The problem is the same with and without vram simm's, if exists a issue is on the vram onboard
Posted by: Byrd on 2015-10-28 15:07:32
Check the VRAM.
Or try a nubus video card.
Posted by: marmotta on 2015-10-28 15:44:08
Or try a nubus video card.
Unfortunately I do not have
Posted by: 360alaska on 2015-10-28 15:58:17
Do you have vram modules installed? Take them out if you do since the logic board has vram onboard...
Posted by: TheWhiteFalcon on 2015-10-28 16:10:10
To my knowledge no Q700 has needed a recap, so you can understand why we doubt that's the case.

Try a different monitor and cable.
Posted by: marmotta on 2015-10-28 16:18:11
To my knowledge no Q700 has needed a recap, so you can understand why we doubt that's the case.

Try a different monitor and cable.
I use a Apple Multiple Scan 720, with powermac work perfect

@360alaska

I already tried with and without vram simm, no difference.
Posted by: TheWhiteFalcon on 2015-10-28 16:19:10
Just because it works with a Power Mac doesn't mean it'll work with your Quadra.
Posted by: marmotta on 2015-10-28 16:48:08
Just because it works with a Power Mac doesn't mean it'll work with your Quadra.
:O  It 'really possible?

........If I try a lcd with db15>vga converter?
Posted by: uniserver on 2015-10-28 19:35:19
there could be a dead tantalum. 

can you take some good quality pictures of your main board and maybe we can have a look and maybe spot something wrong?
Posted by: sstaylor on 2015-10-28 19:55:59
I have run a Q700 with an LCD monitor and an adapter, so it's definitely possible to do.  Whether you have a good adapter or not would be the question...
Posted by: marmotta on 2015-10-28 23:37:35
there could be a dead tantalum. 

can you take some good quality pictures of your main board and maybe we can have a look and maybe spot something wrong?
Yes, is probably. I have tried with the tester (in continuity):

The two caps near psu socket and the caps load energy from tester.

The small five caps near power swich, three is good, one measure "0", and another one measure a fixed value (all other have a variable value... load energy).

Two caps is damaged?

This is a picture of the motherboard before cleaning
Posted by: unity on 2015-10-29 00:27:17
Try the VRAM in pairs. Just a guess, but I think they can go in two at a time since there are six slots. So just try two, then remove those and try another two.

edit: Yes, they can go in pairs. I just checked mine. In mine, the pair is in the two slots to the left as you look at the picture you posted. So the slots furthest back.
Posted by: marmotta on 2015-10-29 01:05:06
Try the VRAM in pairs. Just a guess, but I think they can go in two at a time since there are six slots. So just try two, then remove those and try another two.

edit: Yes, they can go in pairs. I just checked mine. In mine, the pair is in the two slots to the left as you look at the picture you posted. So the slots furthest back.
Thanks, but I have a vram on-board (512kb) and without vram simm's the problem is the same. 
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