G3 iMac PAV

[weirdlookinguy]

Does anyone have any experience with the PAVs on slot loading (Rev. E and later) iMacs? Not the rev. A-D iMacs, those use a completely different design.

I've got a 2000 iMac G3 350Mhz. 160 RAM, 10gig drive that I salvaged from a dumpster eMachines. One of these:
http://www.everymac.com/systems/appl.../imac_350.html
These iMacs have no fans in them (!) and relied on convection cooling for the sake of fashion and quiet operation. These things run incredibly hot! Typical Apple decision, putting form ahead of function. These things take 120V into the PAV (Power/Analog/Video), which is pretty much the chassis for the monitor part of the iMac. The motherboard is then fed 12v/5v/etc through the DCU (Down Converter). So pretty much, the computer portion of the iMac gets its power like this:

120V Wall-->PAV-->DCU-->Motherboard

Anyway, these iMacs have an extremely high failure rate. Usually the DCU or the PAV dies according to Google. I cracked mine open and saw the cause of death immediately:

The DCU and PAV are both completely populated by 85C G-Crapxon and Sh'itscon

The CRT, PAV, and DCU are all manufactured by LG.

Anyway, on my particular iMac, the screen kinda shimmers when I run it at 1024x768. It's unnoticeable at 800x600. I notice it happens mostly when there's heavy HDD activity, but sometimes it happens even when the HDD is idling. I was wondering if anyone with experience on these could tell me what's up? My gut feeling is that the DCU is on its way to shitsville and isn't isolating the PAV very well from the motherboard. Thoughts?

Recapping this one is gonna be a bitch, but I have to save it. My school got iMacs when I was a 2nd grader and I wanted one sooo bad as a kid since I used them all the time at school. iMacs stand out as a significant icon of my elementary-school years. I bought the one I have off Craigslist and it makes a decent music machine for my room running OS X 10.3.9 and iTunes 7.6.

[weirdlookinguy]

Update: It's not really shimmering, more like very very hard to see lines flickering and running up and down the screen. Kinda looks like interference on an analog TV. It's very, very hard to see unless you look really close and know what you're looking for, and is impossible to get a picture of.

EDIT: Also, it's only noticeable when large white objects are shown, like when I open a text editor or a new tab in firefox.

[weirdlookinguy]

Update 2: It's barely noticeable when running at 800x600. It's VERY noticeable at 1024x768, and the image is actually shaking up and down.

Could it be a bad fly? Rev. A-D iMacs were known for Flyback failures, but Rev. E and late revision iMacs are known to have bad flys sometimes too. This iMac is a Rev. E, just for the record.

[weirdlookinguy]

OK, OK, Last update I swear!

It might not be hardware related.

I booted into MacOS 9 just for shits and giggles and the issue is NONEXISTANT! I cranked it up to 1024x768 and let her sit for a while... nothing. I heard that Apple had some batches of iMac where the graphics chip and the heatsink weren't lined up properly or something like that, causing overheating of the chip and funky graphics issues. Since OS X probably taxes the graphics more than OS 9 does, maybe that's it? I'll check it out tomorrow and update you guys.

Anyway, in the meantime, here's some pics. The original CRT iMac definitely has to be my favorite computer of all time

[Scenic]

lucky you (well.. sort of )

my iMac is a Rev. A one...

G3 233MHz (OCed to 266MHz)
256MB SD-RAM (2x128MB SO-DIMM notebook sticks)
Quanta Storage (QSI) Combo drive because the original drive died..
20GB Seagate HDD ... because the original one died...
and guess what? bad flyback... so i soldered myself a D-Sub VGA out...(because the original one... uhm..wait.. )

i keep on fixing stuff on it, but as soon as i fix something, something else craps out
now the PRAM battery is empty... resulting in OSX always complaining that the date is set to 01.01.1970 *grrr*...

not to speak about the extreme waste of space (iMac with non-functional CRT + extra LCD next to it..)

well.. it does look cool... but thats more or less the only positive point


there is actually a site of a guy who described how to put the tray-loading iMac mainboard (for the maccies: logicboard :P) into a uATX case and how to rewire an ATX PSU for it... but i'm just too lazy to do all that for a 233/266MHz machine if i can just use my "hackintosh".. (x86 PC with OS X 10.5.5)... *cough*


edit:

Originally Posted by weirdlookinguy

OK, OK, Last update I swear!
[...]
I'll check it out tomorrow and update you guys.

HA!

[weirdlookinguy]

I had an original 233 Bondi Blue (Rev. A) for a while too. My flyback also went. Replaced it with a generic and it worked well for a few months, but then I traded it in for this one.

Yours is a Bondi too right? Mine was one of the very first... it was even made in the USA by Apple (right before they started contracting these out to Foxconn in China).

[Scenic]

yep.. bondi blue (i still think its more green-ish)

manuf. date is Aug. 19th 1998



selfmade VGA out..



this kinda screams "reeeetrooooo"



redneck VGA out wiring job



original connector is still there...


that cheapo QSI Combo drive.. the only laptop drive i had here which is bootable in this mac... o.O




oh and BTW: the max. RAM in your iMac is (IIRC) 512MB... i'd go for it as its normal 168Pin SD-RAM AFAIR.. (unlike mine which uses 144pin notebook SD-RAM and maxes out at 256MB (2x128) .. everything bigger (even 16-chip low density 256MB modules) are just recognized as 128MB or it doesn't "POST" at all)

[weirdlookinguy]

Yup, that's just like the first iMac I had, except mine was made in September 1998 and in the USA. I guess Apple was both building them here AND contracting them out at some point. I read somewhere that mid-1999, Apple started contracting them all to LG, but my mid-2000 slot loader was made by Hon Hai (Foxconn). Weird how yours was made in Singapore.

How does OS X run on that? It's surprisingly useable on my 350 w/ 192mb of RAM. You have a slower CPU but more RAM though...

[Scenic]

it still has OS X 10.2.8 on it... runs OK..
thought about updating to 10.3(.9) but now that i got a Powermac G4 400MHz.. :/
would be a waste of time..

guess i'll rip it apart some day and put the parts on ebay..

has been standing around (and always in the way) for about a year now...
only used it 3 times in that time (to copy stuff from apple-formatted HDDs to FAT32 ones using USB HDD adapter thingys by the friendly ebay china guy lol)

maybe i'll use the casing of that iMac to build an intel Atom-based hackintosh with one of my 15" LCDs that no one wants to buy anymore..