840av ports and where to get video ram?

[sunder]

So, as I posted in the Conquests forum, I was able to get an 840AV motherboard working recently, but I notice the specs say this machine has s-video ports. These sadly look identical to ADB ports to me. Can someone who owns this machine tell me which is s-vid in and which is s-vid out?

Did Apple ship any software for video capture with this machine? If so where can I find it?

Also, where can I buy video RAM SIMMs for this beastie?

[Byrd]

Svideo and ADB ports use the same pinout/connector, those on the motherboard itself are ADB, whilst the 840AV (and most AV Macs) have a small breakout box with Svideo, composite, audio in/out. Perhaps your board didn't come with this part? You could probably make your own if you had the correct pinouts.

Interestingly, if you ever need an ADB cable to connect a keyboard or mouse, an svideo cable will work just fine

Looking forward to your 840AV case mod! You could try for an 840AV pizza box

JB

[beachycove]

No it doesn't. The 8500, for instance, is like that, but not the 840av.

The svideo ports are those adjacent to/ either side of the monitor port. I forget which is which, but it does not have especially wonderful video capabilities anyway, so I would not get your hopes too high. It is much better at audio than video.

The separate ports on the rear that have been spoken about are RCA jacks. These are just plugs, and there is no circuit board associated (leads go directly to the logic board).

[sunder]

Yeah, I saw the composite ones, they're the same connector as PC jumpers, or PC LED connectors, so those are easy.
I found a service source PDF for this machine, but it's only how to take it apart and swap boards/drives, so it's kind of useless.

I do notice a problem with this board, I can't always boot it up, but if I do a PRAM reset from the keyboard, it always boots, so maybe the PRAM memory is bad. Or maybe something's draining the battery? Not sure, will have to dig deeper.

Well, at least I can use the video out to a capture board on another machine and capture video. Then again, I could just install a VNC server on this thing and get some program to capture video that way.

Nope, I literally only have the motherboard and power supply from the 840AV and nothing else.

I have an old 100CD Jukebox that's nice and big. If I can mount the 3.5" and 5.25" drive enclosure metal parts from an old PC case, I think it'll work out nicely and it'll look hawt, as the juke is a nice shiny black case. Maybe I can rewire some of the buttons from the jukebox for various functions like reset/programmer switch or even power.

If anyone knows a source of VRAM SIMMs that would rock as I can only get 8 bit video out.

And yeah, RAM doubler was giving me 96MB. This machine has a total of 32MB, which is plenty respectable for a machine of this age.
Isn't amazing how back in 1995 32MB was like 32GB is today?

[Byrd]

Ah bugger sorry got my port layout confused, didn't want to drag my 840AV out of the cupboard (even if it is 1metre away from where I type this).

My 840AV exhibited similar problems when I got it (a few years ago, in bad condition) - it wouldn't start up every time, or not chime/black screen etc. Leave it be for a few hours and it'd boot up fine again, could use it for hours, but if I had to restart it'd play dead.

I was elbows deep in fixing two SE/30 boards at the time, so ended up replacing the caps on the 840AV as well with Tantalum replacements. I found replacing the caps on the 840AV a bit more fraught - they seemed more fragile to remove - but was able to do the job OK and the beast works fine now. I'd also check/clean your RAM contacts, etc.

JB

[sunder]

Hi Byrd, do you remember which caps you replaced? Or at least in what areas?

[beachycove]

Both my 840av boards exhibited these signs of bad caps as long ago as 2005, so it is to be expected. In my case, washing the board fixed the booting problem, though obviously it was a short-term solution. However, 5-6 years is not bad as a short-term solution.

[ianj]

I've been through a fair bit of 840AV logic board drama myself. They are touchy, but getting the capacitors replaced seems to resolve most issues. As for keeping S-Video and ADB sorted out... just remember that ADB is all the way on the bottom and your S-VIdeo ports flank the display connector.

If you want (V)RAM, memoryx.net is a consistent and cheap source of RAM for older computers.

[zuiko21]

I would NOT recommend memoryx.net (neither their subsidiary welovemacs.com) -- poorly made modules, unreliable, extremely bad customer service