MDD2003 graphics booster, too good to be true?

[SnakeCoils]

Hello to you all,
recently I have stumbled upon a strange thread over Macintosh Garden site where a guy named "SkyCapt" seems to have discovered a way to significantly boost up the GPU performances of a MDD2003 populating the memory slots with three 1 Gb DDR sticks where the first two are used by OSX and the third by the GPU as stealth accelerated extension of its onboard memory but all this magic happens only if the PowerMac is faked (thru OpenFirmware declarations) to have a Machine ID of "PowerMac7,2" instead of the usual "PowerMac3,6" and only if it is a MDD2003 model.
Since I was at the same time skeptical but also curious I have done for fun some experiments following the thread guidelines but while I was able to install and run the 10.2.7 G5 edition on my MDD (and I have also tried on a FW800) I have not experienced any improvements over the usual speed.
I have also tried to play the suggested SEGA's game "Typing of the Dead" (a japanese 3D horror splatter where you must kill hordes of zombies typing their name as fast as possible) because this games seems to benefit greatly from this acceleration but I have seen almost no differences between a regular G4 install and a fake G5 3 Gb install.

The thread I am talking about can be found at the following link and I wonder if someone other than SkyCapt has succeeded in making this trick functional... I mean, if it is a later April's fool joke (and I feel it could be since it would too good to be true) it is really well written!

SkyCapt's Macintosh Garden thread

 

[Amethyst1]

Sounds like a load of fanboi BS to be honest.

 

[SnakeCoils]

Sounds like a load of fanboi BS to be honest.

There are many statements in his thread largely inaccurate, for example the assumption that only the MDD2003 machine can recognize 1 Gb RAM sticks while it is possible (and I have personally verified this) to install them on all the FW400/FW800 MDDs. And this "hybrid" G4/G5 motherboard he talks about is something I never heard of, and he does not provide any proof of its existence (no photos, no screenshot, no benchmarks...) and finally how can a DRAM access be faster than GPU's local VRAM? I am not an engineer but commons sense suggests of not.

 

[casperes1996]

There are many statements in his thread largely inaccurate, for example the assumption that only the MDD2003 machine can recognize 1 Gb RAM sticks while it is possible (and I have personally verified this) to install them on all the FW400/FW800 MDDs. And this "hybrid" G4/G5 motherboard he talks about is something I never heard of, and he does not provide any proof of its existence (no photos, no screenshot, no benchmarks...) and finally how can a DRAM access be faster than GPU's local VRAM? I am not an engineer but commons sense suggests of not.

On any sensible system it wouldn't be, no. But I mean, in theory you could have a GPU with DDR2 memory attached and the system memory be DDR4, at which point DMA to system memory would be faster. But no in any sensible situation that's bollocks

 

[bunnspecial]

There are some crazy, twisted PPC theories out there and most of them are wrong. A look at the MDD block diagram will show virtually no similarity between it and a G5(where's @LightBulbFun ?).

This is no different from the "hidden features" of DLSD PowerBooks that get trotted out every once in a while or some other stuff.

 

[davisdelo]

... a guy named "SkyCapt" ...

Look through his posts, it's all posturing BS. Everyone that calls him out for proof on all his claims gets a nonsense rabbit-hole response.

 

[AphoticD]

Reality can bend by simply changing one's perspective.

 

[bunnspecial]

Claiming full GPU accel with a Radeon 9600 in OS 9 is enough for me to have doubts.

Getting full accel with CI cards has been a pipe dream of the folks who know OS 9 as well as anyone does for a long time, and there are serious doubts that it's even remotely possible.

 

[Amethyst1]

Look through his posts, it's all posturing BS.

I genuinely wonder why he's wasting his and others' time doing that.

 

[Dronecatcher]

Look through his posts, it's all posturing BS. Everyone that calls him out for proof on all his claims gets a nonsense rabbit-hole response.

That seems to be the standard response when their internal logic breaks down.

I think SkyCapt does see minute changes that initiate his extravagant claims..but the changes are probably incidental - as simple as clearing caches or a reboot.

 

[Amethyst1]

I think SkyCapt does see minute changes that initiate his extravagant claims..but the changes are probably incidental - as simple as clearing caches or a reboot.

That still doesn't explain why he's asserting that e.g. the MDD2003's board is basically a G5 one, as simply looking at the board schematics proves that wrong. What's the point of making these ridiculous assertions?

 

[AphoticD]

I wouldn’t write off all of SkyCapt’s theories, there are a few hidden gems. But in saying that, all it would take is a before and after video to give some credit to his findings.

 

[Dronecatcher]

What's the point of making these ridiculous assertions?

No answer to that People will believe what they want to believe regardless of empirical data.

 

[Macbookprodude]

To me, all bogus. Now, if I could use this to boost graphics performance on the Titanium, then I may try it.