Pismo hack (impossible one)

[5300cs]

Okay, someone good with hardware (or just a good understanding) please tell me how impossible it'd be to upgrade the VRAM on a Pismo. Can you detail how nuts it would be to even try it?

I don't want to hear "It can't be done. Deal with it." I want to know exactly how difficult it is. If it were possible, I would so want to try it.

 

[RGunner]

Answer:

cannot be done.

VTBook would allow more display area and higher resolution on an external display (PCM card).

Okay, someone good with hardware (or just a good understanding) please tell me how impossible it'd be to upgrade the VRAM on a Pismo. Can you detail how nuts it would be to even try it?

I don't want to hear "It can't be done. Deal with it." I want to know exactly how difficult it is. If it were possible, I would so want to try it.

 

[Lord Blackadder]

Technically speaking, it IS posssible to locate the VRAM chip on the motherboard and replace it with a larger (But pin-compatible) VRAM chip.

However, without changing the Pismo's firmware (good luck, AFAIK no publicly available documentation for any Apple firmware exists.), the computer would likely either not work at all or only be able to see part of the new VRAM chip (i.e. an amount equal to the original stock VRAM config)

In short, it isn't impossible, but you're going to have to do some reverse engineering. I doubt anyone outside Apple has the necessary info on the Pismo's logic board to make the switch.

 

[dmw007]

cannot be done.

VTBook would allow more display area and higher resolution on an external display (PCM card).

Impossible to upgrade internally. The downside of of using a PCM card is that they are rather expensive ( I think they have one for sale on otherworldcomputing.com that sells for around $250.00). But could be worth the investment depending on your needs/circumstance(s).

 

[dmw007]

Technically speaking, it IS posssible to locate the VRAM chip on the motherboard and replace it with a larger (But pin-compatible) VRAM chip.

However, without changing the Pismo's firmware (good luck, AFAIK no publicly available documentation for any Apple firmware exists.), the computer would likely either not work at all or only be able to see part of the new VRAM chip (i.e. an amount equal to the original stock VRAM config)

In short, it isn't impossible, but you're going to have to do some reverse engineering. I doubt anyone outside Apple has the necessary info on the Pismo's logic board to make the switch.

OK so it is "possible"- but barely.

 

[andy89]

Im guessing this is the same for an imac g3

 

[Lord Blackadder]

Im guessing this is the same for an imac g3

Yep, with one exception. The original Bondi 233MHz iMac had its Rage II video card mounted in a Mezzanine slot and it could be swapped out for a 3Dfx Voodoo 2 card made specially for that computer by Micro Conversions, which gave a decent bump in game performance at the time.

The cards are probably hard to find nowadays, but a little Googling will probably turn a few up.

 

[RacerX]

Yep, with one exception. The original Bondi 233MHz iMac had its Rage II video card mounted in a Mezzanine slot and it could be swapped out for a 3Dfx Voodoo 2 card made specially for that computer by Micro Conversions, which gave a decent bump in game performance at the time.

The Rage II chip set was on the logic board of those iMacs and the Mezzanine slot was always unfilled.

As for finding one of the 3Dfx Voodoo 2 Mezzanine cards for those iMacs, I would make sure that you haven't upgraded your firmware first... the 1.2 firmware update permanently disables the Mezzanine slot.

Apple didn't want the Mezzanine slot used, and this was their way of making sure it wasn't.

On the other hand, you could upgrade the VRAM on those systems from 2 MB to 6 MB by adding a special 4 MB SO-DIMM.



As for the Pismo question at hand... The 8 MB of VRAM is embedded within the Rage Mobility chip set on the logic board. The video chips are mounted on the underside of the logic board which is one of the few places on a Pismo I haven't been.

Even if you did replace that chip set (which would take an expert at soldering), knowing what to replace it with and getting the hardware to work with it once installed would be in the range of impossible.

Also, none of the PCMCIA video cards that I know of worked with Mac OS X.


At any rate, if anyone is going to give this a try, I'm pretty sure that it'll kill the Pismo's logic board. So you should plan on getting a replacement...

You can find one here for $279.00, which is about how much I paid for my wife's Pismo.

 

[RGunner]

VTBook works fine in X.

Check their website.

As for the Pismo question at hand... The 8 MB of VRAM is embedded within the Rage Mobility chip set on the logic board. The video chips are mounted on the underside of the logic board which is one of the few places on a Pismo I haven't been.

Even if you did replace that chip set (which would take an expert at soldering), knowing what to replace it with and getting the hardware to work with it once installed would be in the range of impossible.

Also, none of the PCMCIA video cards that I know of worked with Mac OS X.


At any rate, if anyone is going to give this a try, I'm pretty sure that it'll kill the Pismo's logic board. So you should plan on getting a replacement...

You can find one here for $279.00, which is about how much I paid for my wife's Pismo.

 

[RacerX]

Check their website.

There is a web site that replaces the 8 MB of VRAM on the logic board of a Pismo?


It is a good thing you pointed that out by quoting an entire section of my post rather than the specific line you were referring to. Someone could have mistaken your post as meaning the PCMCIA video cards, but as I had qualified my statement with "that I know of" we can be sure that that wasn't your reason for posting.

 

[RGunner]

whatever...

geez take a pill.

Again from my FIRST answer in this post:

cannot be done.

VTBook would allow more display area and higher resolution on an external display (PCM card).

 

[5300cs]

I don't want to hear "It can't be done. ...

cannot be done.

 

[Lord Blackadder]

The Rage II chip set was on the logic board of those iMacs and the Mezzanine slot was always unfilled.

As for finding one of the 3Dfx Voodoo 2 Mezzanine cards for those iMacs, I would make sure that you haven't upgraded your firmware first... the 1.2 firmware update permanently disables the Mezzanine slot.

Ah, I didn't know that. Anyway the Voodoo is an option for Bondi iMac users, though Voodoos aren't really all that relevant anymore as far as 3D acceleration goes - but more VRAM is more VRAM.

As for the Pismo question at hand... The 8 MB of VRAM is embedded within the Rage Mobility chip set on the logic board. The video chips are mounted on the underside of the logic board which is one of the few places on a Pismo I haven't been.

Even if you did replace that chip set (which would take an expert at soldering), knowing what to replace it with and getting the hardware to work with it once installed would be in the range of impossible.

Soldering surface mount chips isn't really all that hard - but you absolutely should get a junk board and practice before messing with stuff you actually want to use afterwards! And use a good soldering iron - not the $2 horror from RadioShack. ; I prefer to use solder wick - with a little practice you can lift delicate components pretty well - better than with a solder-sucker.

There are a number of IC resellers that will sell you small lots (i.e. one or two) of RAM chips - they're a little overpriced but when you're looking for older stuff they can be reasonable. There's a pretty good chance that you'd be able to find VRAM chips that are pin-compatible (and the same brand/series) with those in the Pismo but 2,4, 8, or 16x the size of the original.

The point is that actually adding the correct VRAM is the easy part - getting the Pismo to see it and use it is where you start really pushing the limits of economy.

 

[skipjakk]

I did some research on this as well

I had researched this a while back, and I can confirm an earlier post that the Pismo's rage mobility chip has the vram embedded in the chip, its not separate, check out ATI's website for the specs. I don't think there was another chip that was pin compatible with the mobility chip.

I think your only option for a speed upgrade is the G4 500-550 7410 chips upgrades that several manufacturers are offering now (think Wegnermedia has them as low as 199.00 now). I did do some additional research and found that some of the later Freescale(formerly Motorola) chips were Pin compatible, but not function compatible. In other words, you could drop them in, but a few of the pins had different functions so probably a hack of some sort would have been necessary.....of course they ran hotter too...

Any thoughts on what it would take to create a processor upgrade for the Pismo that used a pin compatible but non function compatible chip?

Or even way out there, a new motherboard? Think it could be cheap if you mass produced it......

 

[5300cs]

I'm aware of the upgrade cards available for the Pismo, but thanks for telling me. I can't take advantage of them over here (in Japan) because they require the whole machine to be sent to the company. Even with companies that don't require the machine to be sent in, you'll still need to give them your original G3 chip. For some reason, I don't want to do that.

I went asking around over here and those upgrade cards are long but gone. When they were out they were expensive so not that many were made, and the ones that were made, were quickly bought up by G3 PB owners.

I keep looking on auctions, but so far no luck ...

 

[skipjakk]

Check out Wegnermedia

Check out the Wegnermedia card, think its 199.00 but they ship you the daughterboard with the upgrade already installed, and you just ship back your old daughter card......they might ship international....

 

[zen.state]

any powerbook vram mem. chips over 8mb may have different connectors. I don't think the powerbooks had more than 8mb till about the 2nd or 3rd rev. of the pb G4.

in short.. there is a small chance it could work but I doubt it.

 

[zen.state]

this would be a far better thing to add to a pismo. by far one of the coolest 3rd party products for the coolest pb ever.

http://www.wegenermedia.com/pismoslotdrives.htm