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Atomic
19th February 2004, 09:25 PM
Hi all,

For those that like to tinker with their toys, particularly MDD G4's, feel free to check out my site. It's contains essential info to give your MDD a bit of get up and go.

www.bitsandpieces.info (http://www.bitsandpieces.info)

the_argon
22nd April 2004, 06:19 PM
I just joined the dual MDD club and I'm after some info... You are probably the best qualified person for me to ask.

What are the capacities (in cfm) of the stock fans in the MDD G4?

What are your Verax fans rated at?

I am also looking at replacing the fans, hopefully to reduce the noise. But to increase cooling efficency for a possible future overclock.

Atomic
22nd April 2004, 07:58 PM
Welcome to the club :)

Below are the specs for the stock MDD fans:

* Papst 4212H 120x120x38mm - 3400rpm / 108CFM @ 49dB

* Acbel power supply fans (x2) Minebea 2410ML-04W-B60 60x60x25mm - 5300rpm / 25CFM @ 38dB

I have read that Apple has also used Delta AFB0612EH - 6800rpm / 38 CFM @ 47 dBA. I think these were used in the very first MDD's that everyone complained about and Apple subsequently started the power supply exchange program that offered both AcBel (newer version - possibly like the one in my 2003 MDD) and Samsung power supplies.

* Optical drive fan I believe is 60x60x15mm rated at 39dB but need to clarify.

[EDIT] Here are the specs for the optical drive fan - Delta AFB0612HHB 60x60x15 - 4500rpm / 17.3CFM @ 35dB

_________________________________

The fans that were replaced:

* 120mm Panaflo FBA12G12H - 2500rpm / 103.8CFM @ 41dB (bear in mind this fan never runs at full speed - usually about 7V or half speed so I would figure about 25-30dB of noise at normal operating temperature)

* PSU fans - Bought the Verax M11 PSU Kit (http://www.verax.de/verax.php?SID=21139408787772e643&template=catalog_entry&entryid=45). These contain Verax 65201237-KT 65x65x20 - 3700rpm (variable) fans - I don't know the CFM or dB rating however they move a decent amount of air and are virtually silent due to a three phase motor design. You literally need to concentrate and get right near them to hear them in action. I also used these fans on the front and rear grilles along with Verax 80251231-KT2 80x80x25 3100rpm on the rear.

* I have not yet found a suitable replacement for the Optical drive fan hence the stock fan remains.

Having said all this, the quickest and easiest way to make your MDD quieter is to change the PSU fans - they are the major culprit. The best way to get a cooler running MDD without changing any fans is to replace the aluminium heatsink with a copper heatpipe heatsink from a dual 1.42GHz MDD (Apple P/N 076-0983). You can try your local Apple reseller or smalldog.com (http://www.smalldog.com/product/44140).

Obviously I modded both the fans and heatsink along with my fan extension mod (http://homepage.mac.com/paul74/MDDFanExtensionMod.htm) to keep everything cooler.

sillydog701
22nd April 2004, 09:46 PM
thanks Atomic.
I am thinking about reducing the noise of my dual 1.42. I guess I will try to get the Verax M11 PSU Kit.
Is it hard to install?

Currawong
22nd April 2004, 09:56 PM
I remember thinking, when the MDD G4's came out, that they would be the machine everyone abandoned when the G5's, which were vaguely expected, came out. How wrong I am...seeing all this makes me want to own a MDD G4 so I can mod it - it's a better setup for me considering all my stuff that isn't on DVD is on a couple of 80Gb hard drives.

Atomic
23rd April 2004, 01:59 AM
Originally posted by sillydog701@Apr 22 2004, 09:46 PM
thanks Atomic.
I am thinking about reducing the noise of my dual 1.42. I guess I will try to get the Verax M11 PSU Kit.
Is it hard to install?
Not really if your pretty handy with tools. You do need to fully remove the power supply and asscociated wiring looms etc but everything is moulded to fit so well it pretty much fits back in perfectly.

Atomic
23rd April 2004, 02:12 AM
Originally posted by Currawong@Apr 22 2004, 09:56 PM
I remember thinking, when the MDD G4's came out, that they would be the machine everyone abandoned when the G5's, which were vaguely expected, came out. How wrong I am...seeing all this makes me want to own a MDD G4 so I can mod it - it's a better setup for me considering all my stuff that isn't on DVD is on a couple of 80Gb hard drives.
To be honest with you, I waited forever for Apple to release a dual optical drive machine and when they finally did it was at the end of the G4's life. Now they are back to their old ways and gone for one optical drive and two HD's in the G5.

The reason I love my MDD is because of the dual optical drives and because I can run an internal SCSI chain so neatly. Also, the fact that I can fit 4 HD's in there is great. 2 x SCSI discs (15krpm system disk) and 2 x 250Gb storage drives is perfect. I love the fact that I can move my machine (and I do this quite often) and be able to take SCSI speed (75Mb/s :)) with me and ALL my data (572Gb's). Try doing all this in a G5 and you will soon been buried in external drives and cables.

With all of the above plus 4 extra fans, 1 PCI fan and 3 PCI cards, I think my MDD is extremely neat and tidy.

http://homepage.mac.com/paul74/images/06_000.jpg


Yeah I know the G5 smokes my G4 but hey it still does the job extremely well and have no reason to own a G5 at the moment.

Currawong
23rd April 2004, 08:19 AM
Ahh, I have the solution for you - I picked up a Sun 711 SCSI case - it takes up to 12 80-pin SCA drives. I have brackets for 6 in mine, and they are now loaded with 32Gb 10Krpm drives. The box isn't that large (drives are installed in the side, same orientation as the G5 drives, in two columns though). It also has auto-id assignment and auto termination. If it weren't for the noise (I live in a studio apartment and I can't sleep with the whine), I'd be using it now.

Atomic
25th April 2004, 12:57 AM
Was bored tonight and thought I'd have another crack at getting the G4 up to 1667MHz - at last success!

Info, photos and benchmarks here (http://www.bitsandpieces.info)

DianaMurray
30th May 2005, 01:08 PM
Hi

Does anyone know if you can purchase the Verax fan solution in Australia. If not a recommendation for an overseas supplier?

Thanks

napes
30th May 2005, 01:34 PM
Cool site Atomic :)
What doi you reckon the highest 'stable' overclock for a MDD 2x867 would be?

Atomic
31st May 2005, 12:04 PM
The dual 867 MDD operates a 133MHz memory bus. Without touching the CPU jumpers, you can overclock your memory bus and the CPU's simultaneously.

There are a few things you need to know here.

1. If you perform this mod you have to purchase new RAM that is specified DDR 333 PC2700. This operates at the correct frequency of your new bus.

2. This is a much more effective overclock than altering just the CPU speed and leaving the memory bus at 133MHz. You are effectively opening the floodgates a bit more to allow more data to travel to a fro.

3. By performing this overclock, you will be raising the bus to 167MHz and at the same time without performing any additional soldering will also raise your CPU speed to 1083MHz each. This is because the bus multipier remains the same at 6.5 - Therefore 6.5 x 167 = 1083 (actually the true bus speed is 166.66MHz)

4. There is a slight chance that you may need to raise the core voltage but I would try the bus overclock first and see i fit boots - if not, raise the voltage slightly until it is stable.

This mod couldnt be simpler - all you need to do is remove 1 resistor from underneath the motherboard and another resister from the CPU card.

More info here. (http://www.hardmac.com/article.php?id=4)

napes
31st May 2005, 01:17 PM
Brilliant - thanks for that info Atomic.

Seems pretty straight forward though still a bit apprehensive. Last bit of soldering I did was in Uni. Also, I'll have to replace 1gig of ram which'll be expensive.

Finally - what is the operation for raising the core voltage (just in case - like to know every possibility and what it'll require beforehand).

Thanks again for your help. :) I love my ol' g4 and a little speed bump would certainly be useful.

Atomic
31st May 2005, 11:15 PM
There are a series of resistors surronding the voltage regulator. Using the appropriate combination, it is possible to raise or lower the amount of power being fed to the CPU's.

You can view this information and pics at my site (http://bitsandpieces.info/atomic2/Multipliers.htm).

napes
1st June 2005, 12:06 AM
Sweet :) Thanks :)