Quadra 800 / Quadra 840av

[uniserver]

Well so far I can say this case design is not my favorite.

both the Quadra 800 and 840av had alot of rattling plastic pieces in the case when arrived.

The Quadra 800 is clean, and works great. I like the fact they used all quality solid caps on the main board.

The Quadra 840av came from a machine shop, I am still in the middle of working on it,

Its got some serious issues Basically the power supply pretty much exploded It was quite an early 4th of july.

 

[uniserver]

So far with the 840AV motherboard, (using the Q800 PSU)

I've re-capped it. - Haven't washed it yet however.

The good:

KBD power on, will Turn it on!

I get Video,

I get the flashing ? floppy

I can move the mouse cursor around

The Bad:

- No Sound from the internal speaker

- Floppy dead, Tried other Floppy Drive - doesn't even spin the drive

- SCSI does not respond, will not boot a scsi drive.

there could be more, but that is as far as I've got.

 

[IIfx]

I will never understand why apple used the cheap caps on the higher end 840av. The Q800 is a great machine, encased in one of the most annoying cases of all time. (SpindlerPlastic as well!) My Q800 lost its CD bezel recently thanks to those brittle clips.

 

[Unknown_K]

I don't think Apple ever wanted you to open up the 800 series cases anyway. Don't think those surface mount Aluminum capacitors were cheap at the time either.

 

[trag]

I don't think Apple ever wanted you to open up the 800 series cases anyway. Don't think those surface mount Aluminum capacitors were cheap at the time either.

And yet, they used all tantalums in the IIfx...

 

[Unknown_K]

Maybe the higher frequency (40mhz FSB) on the IIfx needed those type of capacitors or the designers just liked them better. Neither type has gone away from use since the 90's (both have evolved a bit). I think the Q650 also had tants, same with the 950?

 

[uniserver]

I'm trying to figure out if particular cap use was purely a cost thing, or if its just the designers (at the time) preference.

My experience with the IIfx, is that there is acutely pads for both Tantalum cap … and pads for the SMT Aluminum Electrolytic.

Witch I thought was kind of interesting…

 

[volvo242gt]

Re: the IIfx, my board has two SMT electrolytics on it... Both of which should be replaced, since there is the usual crud around them.

Anyway, hope you can get the 840's board sorted out so it works properly.

-J