MDD 866 Mods

[Protools5LEGuy]

I've pushed a [email protected] dual module up to 1.750 in to a MDD. It was the last time I felt a computer FAST: Pure speed.

 

You say that just to create ENVY. Are you sure M.A.R.L. do not accept Paypal? I see the same business that Apple is the master: To show a incredible product that every user has to say "I want one".

Did you use a fridge as a box for the MDD@1750? I think the case would melt down...

[MacTron]

in most of your mdd overclocks u are probably using pc3200 ddr 400 ram right?
the machines were originally made for pc2100 ddr266 or pc2700 ddr-333 ram
(2100 for the first mdds i beleive)
which is why using pc3200 ram allows the cpu to go higher..
u have this room for overclocking to be successfull ..
because the ram can match the increased frequency

on a g4 if u use pc100 ram.. theres no way overclock is gonna work
people who have shitty ram and try overclocking will fail

well really its not that the ram is shit.. it just isnt rated high enough to match the territory
that u push teh cpu to.. its "off the map" of what it can do

No at all. RAM speed only has to be taken in to account if you change the main buss speed, not the CPU speed.

[MacTron]

I've pushed a [email protected] dual module up to 1.750 in to a MDD. It was the last time I felt a computer FAST: Pure speed.

 

You say that just to create ENVY. Are you sure M.A.R.L. do not accept Paypal? I see the same business that Apple is the master: To show a incredible product that every user has to say "I want one".

Did you use a fridge as a box for the MDD@1750? I think the case would melt down...

The main MDD fan was connected directly at 12v. Really.
LOL

[supernova777]

No at all. RAM speed only has to be taken in to account if you change the main buss speed, not the CPU speed.

bus speed affects system ram yes u are correct
and cpu increase affect cache ram

Of course the cache chips can be changed, even the G4 chips... it cost between 100 and 200 EUR. But why? I have not ever found a synthetic or real test that shows some benefice of 2MB of L3 against 1MB of L3. My last try was with the xServe CPU...

this is why the man in the article ptleguy was looking at
was talking about taking off his cache ram + replacing them
with higher quality chips.. not larger sized chips.

i cant find the link but i remember reading something about 270mhz?
and the quality of his cache chips.. and how he looked up the spec of the ram chips

[IIO]

haha, resistors under the microscope ... you guys are so anal with your hardware ... just like i am with my DSP code.

[supernova777]

Chris had come with the perfect example. Compare the DA 733 with the QS 733 performance with cinebench or geekbench or OS9benchwhateveriscalled.

isnt the 733mhz DA alot better then the QS?
the QS has no cache... but 733 DA does have it , i think?
diehard was the one who told me the 733DA kicked the QS 733's ass

[MacTron]

I'm talking of 1MB of L3 against 2MB of L3, I'm *Not* talking about having L3 against not having it. In the G4 7450 the pipelining was increased from 4 to 7 stages, so L3 caché is very important here, but 1 or 2 MB? I never could find a difference.
The QS 733 was a marketing downgraded hardware as the MDDs with 133Mhz Bus.

[Protools5LEGuy]

I'm talking of 1MB of L3 against 2MB of L3, I'm *Not* talking about having L3 against not having it. In the G4 7450 the pipelining was increased from 4 to 7 stages, so L3 caché is very important here, but 1 or 2 MB? I never could find a difference.
The QS 733 was a marketing downgraded hardware as the MDDs with 133Mhz Bus.

http://www.everymac.com/systems/apple/powermac_g4/specs/powermac_g4_733.htmlDA
Introduced January 9, 2001 disc July 18, 2001 cost     US$3499 with superdrive and 3000 with CD
http://www.everymac.com/systems/apple/powermac_g4/specs/powermac_g4_733_qs.htmlQS
Introduced July 18, 2001 at US$1699
You pay in feb 2001 3500$ for a 733 and in august 2001 1700 for a 733 HALF!
But the cpu of both 733 cant be more night and day!
1Mb of L3 cache vs no L3 cache on QS

733 DA Geekbench 2 =430-450 http://browser.primatelabs.com/geekbench2/2446079
733 QS Geekbench 2 =400-405 http://browser.primatelabs.com/geekbench2/1360228

Dawn, it is difficult to find test on same OS...

DA 733 was top of the line while QS 733 was low end of line. Same speed 6 month later. I guess some buyer of the DA 733 could have rage over Apple... They paid 3000-3500$ for a machine that was 1700 later...

[IIO]

when the QS 733 came out, the germans keyboards magazine came out with a test of reverb plug-ins and the QS 733 was not faster than the 533 for most reverbs tested. for the steinberg reverb-32 the 733 was even slower compared to the 533 and dual 500 G4s.
you can find noticable differences between having cache vs. none also for soft GL (diablo 2) and G4 optimized fast fourier transform (such as fftw, some max objects or vst plug-ins), and also for the one or other image editing process.

[supernova777]

The main MDD fan was connected directly at 12v. Really.
LOL

is it depending on which pins u draw power from on a 4pin molex that determines the voltage to be 12v vs 5v ?

pic attached is of a 12v connection to illustrator the 4pin molex connector is using only the right most 2 pins
could i use this technique to up the voltage of my fans?

[MacTron]

is it depending on which pins u draw power from on a 4pin molex that determines the voltage to be 12v vs 5v ?

Yes it is.

pic attached is of a 12v connection to illustrator the 4pin molex connector is using only the right most 2 pins
could i use this technique to up the voltage of my fans?

If the fans have variable speed usually receives variable voltage. To increase the voltage of this kind of fans 5v usually is summed (ie: in parallel= variable voltage + 5 volt ) ... but be careful! ...

[Protools5LEGuy]

If the fans have variable speed usually receives variable voltage. To increase the voltage of this kind of fans 5v usually is summed (ie: in parallel= variable voltage + 5 volt ) ... but be careful! ...

From a Molex connector

You can take (without a potentiometer) +5 (red black), +12 (yellow black) and +7 (12-5 red yellow)

[Protools5LEGuy]

Just found some more pictures about the 166 bus unlock

http://forums.macrumors.com/showpost.php?p=18789514&postcount=1



Full post http://forums.macrumors.com/showthread.php?p=18789514#post18789514

[DieHard]

I'm talking of 1MB of L3 against 2MB of L3, I'm *Not* talking about having L3 against not having it. In the G4 7450 the pipelining was increased from 4 to 7 stages, so L3 caché is very important here, but 1 or 2 MB? I never could find a difference.

I agree with Mactron… 1 MB vs 2 MB did not yield as big of a difference as other factors; unfortunately, when my company was testing all of these G4 systems in a real world DAW environments, we did not have an exact platform (G4 model) that only differed by cache. We standardized on the QS933 with 2 MB cache for some client's needs and the single MDD 1.25 with 1 MB for others.  The MDD was clearly the performance winner in the VST arena, but there were other factors like faster PATA and memory architecture, I think the 2 MB on the 933 probably help a smidgin, but again we chose the MDD for the powerhouse and the QS 933 was used in environments that needed to be quieter.  We gave up on the Dual processor stuff altogether at the time to avoid compatibility issues.  After picking the 933 QS or MDD 1.25 as the base system, for VST systems we added cards like the UAD-1 and the power core PCI to get pro results without overtaxing the CPU… this made a VST DAW similar to a ProTools rig… DSP cards helped offset the CPU usage.

Over-clocking sounds great…it definitely adds another level to maximize a DAW.  We just focused on what worked at the time and produced stable and consistent results.  Since the over-clocking also adds a layer of trouble-shooting, we avoided the information that was available at the time (which was very little).  I think of the Over-clocking as real art form, and not for the average users, but I value all of the efforts that have yielded amazing results and made G4s go faster than thought possible

[supernova777]

honestly ptle5guy--
the 167 mhz mod isnt worth the trouble
u can go out and find a used g4 with the factory 167 bus for less then 50 bucks here
theres one sitting at the shop down the street right now for 40$ from my house
why would i risk messing around with the motherboard when i can just check the classified ads;D

[Protools5LEGuy]

honestly ptle5guy--
the 167 mhz mod isnt worth the trouble
u can go out and find a used g4 with the factory 167 bus for less then 50 bucks here
theres one sitting at the shop down the street right now for 40$ from my house
why would i risk messing around with the motherboard when i can just check the classified ads;D

Chris, I would not pay 50 bucks for a motherboard with one resistor less... 
I have changed motherboards on PC boxes since 1998... It is only to find a good guide to take off the motherboard from MDDs.
To unsolder SMD components is not easy, but also is not hard if you practice. I have been using a soldering iron to repair my guitar cables since 1990... I am not an expert, but the practice would lead to do it right as Harrymatic says on the post.
It is confirmed that the only difference in motherboards is the dawn R676 resistor. I wish apple would use a jumper, but that is not the case.

Locate and remove the resistor marked R676 on the underside of the board – it’s near the heatsink under the CPU area. (see photos) You’ll need a fine pencil-tip soldering iron. Make sure that the removed resistor doesn’t get lost somewhere on the board! I didn’t find this too difficult as I do a lot of work with electronics, but if you don’t have experience with SMD components, practice loads on some old PCBs first.

Imagine you can get 2 MDD for 50 bucks, one working at 866 and other 1.25 but with the PSU dead. What would you choose? Ah, you would choose BOTH, because you have the money...That is not my case...

Anyway, here in Spain a working MDD still cost 100 Euros (120-130 USA dollars). Even some original Sawtooth are trying to be sold at 100. And MDD PSU also 100. I wish we have those offers here in Europe, but is not the case...

The iFixIt guides for MDD are not deep, but at least we have the best graphic guide I have found for them:
https://www.ifixit.com/Teardown/Powermac+G4+MDD+%28Mirrored+Drive+Doors%29+Teardown/1624

It is up to the user if it worth to pull out the motherboard from the box. Eventually, if you buy a MDD 166 bus motherboard, you will have to pull out the old-slow motherboard...

Please, if someone swap out a MDD 133 board, and have no interest on it, PM me. I would pay shipping cost in Europe.

[supernova777]

i would choose the 867 and leave it as an 867
which is what i have.. and its fast enough as it is..! really ! i dont notice that its slower then the single 1.25
in fact it has a higher benchmark then the 1.25 single
naturally 2 against 1 cpu

[Protools5LEGuy]

i would choose the 867 and leave it as an 867
which is what i have.. and its fast enough as it is..! really ! i don't notice that its slower then the single 1.25
in fact it has a higher benchmark then the 1.25 single
naturally 2 against 1 cpu

I would be happy with the 866 dual if my last PowerMac were the DA 466, but since I bought the GHz dual cpu module from QS02,  I feel it slower... Once you test speed, you get addicted...

Yeah, the 866 is a good machine compared to Digital Audios, but only on OSX. I feel the MDD with 2 gigs of ram as fast as the QS02 with 1 gig on Tiger and Leo.

But for OS9 the QS02 is faster/more powerful.

I do not force users to do the mod. Just wanted to get all the info in one place. I like stock machines too, but the benefits of pulling out the R676 is too much to ignore it...

[Protools5LEGuy]

167 Mhz is the "native" bus speed of MDDs. (by the way, it can be overclocked to 172 with motherboard oscillator change) although some "low end" MDD's were working at 133 Mhz for marketing reasons  (this is easy recoverable via motherboard multiplier resistors settings). Well I never have done it, it is easiest try to acquire the good ones (167 Mhz)

Sorry to bring back an old thread, but I have seen you reference the 172 MHz bus clock a couple time but not sure where you got the info. Very curious if you have URL/doc/etc laying around yet with this info?

The MDD bus can be changed from 133 to 166, just changing some resistors in the Motherboard. But If you already have an 166 Mhz Bus System, The only way to go further is to change the base quartz oscillator of the motherboard.

MacTron: Let's be accurate. It is 1 resistor to be pull of for the motherboard to get 166.

[Protools5LEGuy]

Old article about unleashing the 166 bus on first MDDs
http://www.macbidouille.com/articles/89/page1

Can you tell us if the MacBidole article is well translated? http://macos9lives.com/smforum/index.php?topic=1652.0

Well, for starters, it's MacBidouille!

automated translations always make me cringe...
at least the first bit is correct. the following two should read:

----------------------------------------------------------------------------
Note that changing the bus from 133 to 166 Mhz would overclock the machine to more than 1 Ghz. To avoid this, you must reduce the multiplier from 6.5x to 6x
Watch out !!!!!
To ensure the stability of the machine after changes, it is imperative to have only DDR-SDRAM PC 2700! 2100 simms are to be avoided !!!
Changing the bus takes 2 steps:
1) changes to the motherboard
the photo is the underside of the motherboard.
I surrounded the three resistors in question.
They are in order R677, R678 and R676

For a bus of 133mhz: there is a resistor at each location
for a bus to 167MHz: you must remove R676
(It's about 100% on because I had 2:30 to scan both cards under the microscope and that's the only difference)
So there must be more to it (I have not taken the time to try and ram no longer lends itself to such practices)

Apple has added a second protection on Bi 867 cards: If you change the settings just on the motherboard, it will go to 167 Mhz only if you install a 1Ghz or 1.25GHz bipro card.
(So I'll turn it back to Amber:)
So on the daughterboard pictured, there is a series of three resistors,
numbered as follows.
 167 Mhz Bus:
R27 nothing
R22 nothing
R26 Resistor
 133 Mhz Bus:
R27 nothing
R22 Resistor
R26 Resistor
So it is a security or a lock from Apple
----------------------------------------------------------------

I'll leave it to you to edit the original posts: I have no way to do this...