The Indestructible iMac G5 - Full Poly Mod

**Topcat** · 08-20-2010, 07:31 PM

Re: The Indestructible iMac G5 - Full Poly Mod

Originally posted by ratdude747

mine came in.

it is the badcaps.net poly mod #3. it is a 17"

the solder work was done by topcat and i attest it works great.

how i got it will be secret unless topcat says how.

Not a state secret, so I'll spill it... It was one of the donors. I ended up with 8 of these systems, so what better way to further test than to put a few out into the world. I gave 2 of them away, Larry got one, another friend of mine got the other one. I gave one to my wife, she loves it....loves it enough that she dumped her PC. Lets see, I have one in my home office, I have another in my shop office, one in the lab, another is reserved for my workroom addition when its finished, and I'll use another one out in the shop as well. These are the absolute best internet terminal/email machines. They're small, self-contained, and with the polies, should outlive all of us!

FWIW, this post was made from the 20" shown above. I use the system all the time, its been solid as a rock.

**ratdude747** · 08-20-2010, 09:14 PM

Re: The Indestructible iMac G5 - Full Poly Mod

thanks topcat!

yeah... macs are not too bad... i wpuld not pay full price for one, but this g5 kicks butt.

**weirdlookinguy** · 08-21-2010, 12:13 AM

Re: The Indestructible iMac G5 - Full Poly Mod

Now I really want one!

**ratdude747** · 08-22-2010, 11:58 PM

Re: The Indestructible iMac G5 - Full Poly Mod

i gave up on trying to get leopard to work. dl dvd+r's are soooo expensive! and the compression trick to make it burn to a sl was a waste... it wouln't work in the stock drive (it did a usb dvd-rw dl fine but usb= no boot).

so, i am installing ubuntu ppc 10.04 on it for sh!ts and giggles... maybe that will work better....

**Rick_Hardslab** · 02-26-2011, 04:03 PM

Re: The Indestructible iMac G5 - Full Poly Mod

Sorry to be grave digging but I'm really curious how the poly caps are holding up and also on your diagram you seemed to indicate that you replaced the 5 16v caps with 330uf but the originals were 1000uf, This is surprising that 1/3 the original value works.

**Scenic** · 02-26-2011, 04:17 PM

Re: The Indestructible iMac G5 - Full Poly Mod

it's the ESR that matters, not so much the capacitance.

i've seen this on a bunch of PC motherboards too.
"low end version" of one board had 4x 16V 1200uF "classic electrolytic" VRM input caps (on 12V) while the more higher end / expensive version of the same board used 4x 16V 470uF polymers instead.

that's 4800uF for the lytics and 1880uF for the polys.
ESR on the polymers is still quite a bit lower than on the lytics though

edit: while looking at the first post again i thought about something..

do all those blue marked polys in the very first pic in post #1 necessarily have to be 6.3V ?
as in: is the actual voltage they're on really that high?
if not, one could also use 4V or maybe even 2.5V polys if the voltages are low enough.. but i kinda doubt it..

**Th3_uN1Qu3** · 02-26-2011, 05:04 PM

Re: The Indestructible iMac G5 - Full Poly Mod

As long as there is enough capacitance to form an effective lowpass filter at the switching frequency, the board will work fine. This can be calculated, but there is no such calculator online and i'm too lazy to throw a spreadsheet now. The only reason why a lot of capacitance was traditionally used in CPU supplies was because they had high ESR and/or dissipation capability. As capacitors get better we need fewer of them.

2.5v polys can be used on the CPU Vcore.

**Rick_Hardslab** · 02-26-2011, 07:57 PM

Re: The Indestructible iMac G5 - Full Poly Mod

The bulk (twenty some) of the caps are 6.3v because they are floating on the 5v rail. You always want a cap to be rated to survive more voltage then you are trying to store in it, as overflow is quite destructive. The 5 16v caps are for the 12v rail.

**Scenic** · 02-26-2011, 10:14 PM

Re: The Indestructible iMac G5 - Full Poly Mod

i've never seen one of those iMacs in person, so idk what voltage rails the caps are on.
was just a random thought (the lower voltage caps)..

**Topcat** · 02-27-2011, 04:11 PM

Re: The Indestructible iMac G5 - Full Poly Mod

All the test subjects are holding up well. My wife's never gets shut off, still cranking along fine.

**ratdude747** · 02-27-2011, 06:44 PM

Re: The Indestructible iMac G5 - Full Poly Mod

mine is rock solid. no complaints.

**TheLaw** · 03-08-2011, 10:33 PM

Re: The Indestructible iMac G5 - Full Poly Mod

Kinda want to buy a broken one off eBay now...What kind of power supply do you need? Is it proprietary bull---? or standard plugs?

See if I can get a Mac running for under $200?

EDIT: I see it is a proprietary. If I buy a dead PSU, is the problem usually bad caps or?

**Topcat** · 03-08-2011, 10:36 PM

Re: The Indestructible iMac G5 - Full Poly Mod

^
Its definitely proprietary. the iMac is an all-in-wonder system. Plug is the same as a regular 20-pin ATX, but an ATX PSU won't power one. You can get broken iMacs off ebay all day long for 200 or less. A good condition 17" imac in need of recapping averaged about 100 bucks last time I looked at them.

**Toasty** · 03-09-2011, 07:37 AM

Re: The Indestructible iMac G5 - Full Poly Mod

Make sure you get one with ALL its parts. Many of these are "such-a-deal" with no hard drive, no drive carrier, no RAM, no keyboard, no mouse, no OS or discs, no Superdrive or bracket..... for $200!!! PLUS S/H of only $90!! . . . . Are you nutz?!?

Apple Keyboard $35-$50, mouse another $10-$12
Hard drive $25-$50
Drive carrier $15
RAM $22 each or $45 for 1 Gb (2 pcs 512)
Superdrive $100 new ... $20-$35 used/refurbished
Superdrive bracket $15
OS X 10.4 Tiger $10-$50

A complete system with -all- its parts from an -original owner- in the -original box- can be had off of Craigslist for $100-$150. You just have to pick up. I just got a 20" system like that for $110 but I had to drive 40 miles round trip...

Be careful and ask a lot of questions. Your looking for answers like "It was my dad's or mom's". Make sure the casing, stand and back cover are intact, no chips, cracks, or broken lock down clips. The screen should be perfect. No scratches no dead pixels.

Toast

**TheLaw** · 03-09-2011, 05:19 PM

Re: The Indestructible iMac G5 - Full Poly Mod

Hmm....I wish I could just use the motherboard and hook up regular PC hardware to it which should still let me use Mac OS X. Ehh...Maybe I'll just try one of those lovely Optiplex mods. I need a cheap HTPC. >.<

**Scenic** · 03-09-2011, 05:30 PM

Re: The Indestructible iMac G5 - Full Poly Mod

you can install OSX on pretty much any modern x86 PC if you want to

http://wiki.osx86project.org
http://www.insanelymac.com/forum/ind...?showforum=178
http://tonymacx86.blogspot.com/2010/...c-os-x-on.html

**TheLaw** · 03-09-2011, 05:47 PM

Re: The Indestructible iMac G5 - Full Poly Mod

I've always found the legality of those a bit sketchy, though I don't believe having closed software is cool either.

**Scenic** · 03-09-2011, 06:15 PM

Re: The Indestructible iMac G5 - Full Poly Mod

there are packages out there which use a retail OSX DVD (and encourage you to buy one ; they're pretty cheap).
basically those installer packages consist of a loader for the retail DVD (including patches) and a bunch of kext's ("drivers" in mac-speak)..

no need to download sketchy prebuilt .iso's via torrents or crap like that.. (iAtkos, Kalyway and whatever they're all called..)
the last link in post #36 is actually about one of those loader-packages

The Indestructible iMac G5 - Full Poly Mod

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Related Topics