Big Plans for an MDD - Help Appreciated

Posted by: waamatt

Big Plans for an MDD - Help Appreciated - 03/29/06 09:40 PM

So, last month I bought a Dual 867 MHz Mirror Drive Door PowerMac G4. It has 512MB of RAM and is pretty much stock all around (it has an AirPort card in it already, which is good, since I share internet service with my neighbor via wi-fi). In general, this machine is great. It's my way of finally upgrading from a 400MHz G3 iMac DVse (and to a lesser extent, a 700MHz G3 Dual USB iBook (16MB video)). Naturally, I want more...

I have big plans for this machine as it's my first Mac that's a) actually mine AND b) not an all-in-one or a laptop.

In addition to simple changes like more RAM and a new video card and a couple other expansion cards, I'd like to make cooling modifications (more and new fans), overclock the processors, and overclock the system bus speed (which will inherently overclock the processors, apparently).

Now, after doing a great deal of research on this matter, there are still a number of things I'm in the dark on. I'm not some kind of computer science wiz so I won't pretend to know how resistors truly work (I get the general idea), or even what the ones in my machine are rated at (if that's even the right way to say it). I don't understand a lot of things about electronics*, but slowly I'm changing that (and happily, because learning is so much fun when there's no school involved).

I guess I should give an exact list of what I'd LIKE to do, and then explain where I'm confused.

1) (This step is already done) Add a bigger, better hard drive (for a total of two HDDs) - I put in a Maxtor 200GB 7200RPM ATA133 drive with a 16MB buffer. It runs great so far... The other drive is a 60GB IBM, presumably 7200RPMs with a 2MB buffer (ATA100). I may eventually reformat the 60GB (it's unused right now) and give it a partition to install Linux on (not sure which distro yet...) for fun and maybe development testing purposes.

2) Max out the RAM (2GB unless the max can be overcome somehow) with low-latency RAM (I have my unfounded reasons :teeth:) with heat spreaders on 'em. I won't do this until all overclocking is done due to the higher bus speed requiring PC2700 DDR SDRAM (or faster, really, but it won't run faster than the system can use - which I'm sure you all know). By low latency I mean, preferably, CL2. I figure, why not?
(If that 2GB cap can actually be overcome, I'd very happily put in 4GB and start doing some audio and video work.)

3) Overclock the system bus from 133 MHz to 167 MHz. I've read this requires buying the processor daughter board (can we call those dabo's?) from a 167MHz bus'ed MDD/FW800 machine. I don't want to do that. The difference is, what, one resistor on the dabo (heehee)? So why not just make that change?

4) With the bus OC, the processors will jump up to 1.25 GHz, right? I don't know what my 867's are actually rated at (apparently many were 1 GHz models, underclocked to meet demands for the 867 models), but I might not be comfortable with a massive OC, so dropping them down to an even 1.0 GHz might be my ultimate course of action. Naturally, I can run at 1.25 for a bit and attempt stress tests. If neccessary, I'll up the voltage a bit, too. Hopefully some day there'll be an MDD dual processor upgrade in the 1.7-2.0 GHz range. That'd be rockin'!

5) Fans! The fans in the machine are, apparently, the ones from Apple's replacement program, but they're still loud. My dad came by shortly after I got this MDD and said it's quieter than his Digital Audio 733 MHz G4. It's louder than his Dual 2.7 G5, so that's kind of sad to me... Actually, when more fans in the G5 kick in, it's a lot louder than my MDD! First and foremost then, is replacing the PSU fans, side door fan, and main, large fan. If possible, I'd like to put one of those pretty copper heatsinks in to replace the stock, finned aluminum one. QUESTION: Can you actually put the copper heatsink on non-FW800 series MDDs?
In addition to that, I'm willing to add more fans (quiet ones) if it actually reduces noise by keeping the whole system generally cooler. Fans on top of the heatsink? A-OK by me. Fans at the bottom of the front of the case? Cool (it looks neat from the underside of the machine too). A PCI card fan? Sure! Why not? I'm probably going to take the speaker off and mount it into the top of the case to allow air to pass through the speaker grill. (I have a pair of Apple Pro Speakers and they sound great to my ears.)
The goal here isn't so much heat - my room rarely ever gets hot. Even with three or four people hangin' out watchin' movies on my giant bed (or playin' video games), the room stays pretty cool. Good ol' San Francisco property located near Lake Merced... Woah, I got WAY sidetracked. The goal here isn't so much heat reduction, but noise reduction. I often find myself using my computer while my wife is sleeping. Oh, and putting the tower under my desk isn't a good option (It'll get kicked... a lot).
Oh, this leads to one more QUESTION: Is my power supply strong enough? It's an AcBel (?) with a lot of Chinese characters on it. API1PC36? AC Input 100-127/200-240V~,7.0A/3.5A (some Chinese characters) 50-60Hz. DC Output it notes for +5.0V and +3.3V that there's a 108W Max.

6) Expansion! I'd like to add a USB 2.0 card, a second optical drive (for disk to disk copies and so I can put my external burner back with my old iMac DVse), and uh... I guess that's it. I suppose a video card upgrade could be considered expansion (it does go in card slot, after all). The USB 2.0 card I looked at (a Keyspan model, 4 ports) has an internal port. QUESTION: Could I then use that internal port to, say, power something inside the case?
As far as graphics cards, I'm a bit lost. While I'm sure an ATI Radeon 9800 Pro Mac Edition (128MB) would be great for what I do (which includes playing World of Warcraft and VERY few other games), they cost a lot. And, if I'm going to spend over $250, I might as well spend closer to $300 and shoot for something better. This might require flashing a card (time to buddy up with some PC users...), or hacking apart the pins on some card to make it fit in the AGP4x slot. Yay!

So, I hope my post wasn't too confusing. Please bear with me - I'm a newbie to stuff like overclocking and fan mods. Soldering? I might outsource that job to my dad (who, conviently, lives very close to me).

I'd also like to pretty up the machine's guts by changing ribbon cables to braided cables and, well, cleaning the parts. Computers get so dusty!!!

Thanks in advance to all of you and to whom it concerns, I really appreciate this site even existing.

Oh, PS: When I start working on all of this, I'll document it all and make a mod guide/article (which I'll also put on my own site).
Posted by: macDeviant

Big Plans for an MDD - Help Appreciated - 03/30/06 11:08 AM

Just wow...! But hey, at least you know what you want to get done. good luck to you. Also if
you are getting a USB card that has an internal port you could run an USB extention cable to the front of the case. Just an idea. I use the front ports on my G5 constanlty and it's a pain in the neck to try and get to the back of my machine all the time
Posted by: Waragainstsleep

Big Plans for an MDD - Help Appreciated - 03/30/06 01:43 PM

I have an MDD which was a single 1GHz FW800 with 768MB RAM and a 133MHz bus.

It still has the 133MHz bus, but is now a dual 1GHz with 1.75GB RAM and a DL burner.

I have added a USB2.0 card with an internal port, but I don't use the internal. Just needed 2.0 for my Nano. I do now have a plan for the internal, but I'll save that for another time.
I'll address your other points one by one:

1: You did this already.

2: The RAM limit is not something you can get around. Its a hardware limit imposed by the configurations of RAM modules the memory controller can address, and the number of RAM slots. The only way around it would be to replace the memory controller, add more slots, or build custom RAM modules. None of these are practical unless you know how to redesign a logic board or design RAM sticks. If you can do this, you can probably afford much faster kit to play with.

3: This is something I was interested in and cast feelers around for a while back. No-one could help me out with precise instructions, though I did find one guide from a slightly newer machine. I did't want to risk this sort of mod in case the parts used in the guide differed from my own. This mod is especially attractive to me for the following reasons:
There were a number of machines running a 167MHz bus before mine, so the chances are mine was downclocked from its true potential, and will run happily at 167MHz. (this is not necessarily so true of the CPUs).
Upclocking the bus not only boosts the bus. A faster bus means potentially faster access between CPU and drives or AGP/PCI cards. It should also upclock the RAM if the RAM is fast enough (most of mine is pc3200/400MHz or pc2700/333MHz, rather than the stock pc2100/167MHz). The CPU's clock speed is determined by multiplying the bus speed by a number which can be determined on the daughterboard (or in some machines the firmware). The number is called the multiplier. Since we are talking about the bus, you can see that my multiplier is 7.5. (7.5 x 133 = 1000) If I up the bus to 167MHz, my CPUs will jump to 1250MHz.
So a faster bus = faster CPU, RAM, drives, graphics, and other connectivity. Not bad if you can do it. Let me know how you get on if you try this. I forget the site I found, but it was australian if that helps.

4: If your bus is 133MHz, your mulitiplier is 6.5. If you clock up to 167MHz, you'll get 1085MHz. Shouldn't be a problem, especially if you add fans.

5: I'll leave fans to someone else, as I haven't bothered to play with mine aside from adding one to my graphics card. Others here know alot more about fans.
I mentioned USB cards. You can power something from the internal. USB is 5V and the pinouts are readily available online, so all you have to do is chop one end off a USB cable and wire it to whatever you want. Many fans will run on 5V.
Graphics cards are also probably best left to others, though I have fitted an nVidia GeForce FX5200 from a G5 to mine, and bolted a fan on it before overclocking it. See my mod guide if you want more about that.

Thats all the wisdom I have to pass on. Best of luck.
Posted by: JediJoker7169

Big Plans for an MDD - Help Appreciated - 03/30/06 04:56 PM

¡Díos mío! Is that not the longest post yet?!!!
Posted by: anil8tor

Power... - 03/31/06 03:49 AM

Great post! I would think the stock power supply would be a bit strained by all those fans. You may want to do an ATX mod, or perhaps add a second mini supply just to power the fans. Sounds like you have a good handle on things. Take advantage of the experiance and advice here at Macmod, some of these guys are truly artist when it comes to modding and over-clocking.
Posted by: waamatt

Big Plans for an MDD - Help Appreciated - 03/31/06 01:00 PM

Thanks for the responses everyone (I thought I had auto-email notifications for replies, but I guess not, so I just noticed all of this today).

Without prior experience with it, I don't see a reason why I can't just bump the bus speed up to 167 MHz. It's two quick solders (one on the mobo, one on the dabo). I haven't been able to find any info online of anyone else doing that. Everything I've seen about bumping up the bus speed has involved buying the daughter board from a FW800 model that was already 167 MHz. Yay...

Maybe Mike from has some info he can pass on to me (which I'd then relay here)... Time to email him and see!

Oh, and as for the graphics card. I'll settle for a stock Radeon 9800 Pro Mac Edition (128MB), but if I can safely/affordably get something better, you better believe I will! : )
Posted by: waamatt

Big Plans for an MDD - Help Appreciated - 03/31/06 03:04 PM

OK... Some info that I hope is accurate:

I seem to have misunderstood in regards to using 167MHz bus speed dauhgter boards in conjunction with a bus speed mod on the mobo to get the 167Mhz bus to work. That's only if you don't want to make mods to the daughterboard.

The only question at this point is, what are the resistors rated at? For the clock speed multiplier resistors, they're 1k ohm. The voltage ones are 47ohms. The bus speed ones? I have no clue.

Also, on the daughter board, the resistors for the spots marked R27, R22, R26 in that order should be empty, empty, resistance. 133 is, in the same order, empty, resistance, resistance.

Hope that info is helpful. I can't see the resistors on the daughter board to guage their rating without pulling off my heatsink, and I'm not going to go that far without doing pretty much all of my overclocking. AND, before I do that, I need to order PC2700 RAM.
Posted by: maestro

Big Plans for an MDD - Help Appreciated - 04/03/06 06:20 AM

Cheers for one of the longest posts ever! Anyway, with all that info, its easy to help out. You cant get past the ram limits which was said and that is true. 2GB should be plenty and if not, you should think of moving to a G5. The bus speed increase has been done with success, so that should be ok too. As for the resistors, I personally do not reuse them. You can just put deforster pen marks on it and change the resistance by how much you add (use a volt meter). I woudl not worry about that though, I usually just solder them together and dump the resistors. All of the bus/cpu/voltage controls are on the daughter card. This model has a 450w psu, so I would not worry about running out of power. Fans will not use much anyway. I have to take this time to plug water cooling. It would be great for MDDs and give you more headroom to overclock and its just plain sexy.

Good luck and keep us posted.
Posted by: waamatt

Big Plans for an MDD - Help Appreciated - 04/03/06 02:28 PM

Again, to everyone, thanks for the replies. (Actually, did I already say thanks?)

I'm weary of home-brewed water cooling. The last thing I'd want to do is sink time and money into this machine and then have the water cooling leak. What a disaster that'd be!

I'll settle for loads of quiet fans and not be too agressive with the OCing. If I can hit 1.25 GHz without any issues (like individual processors going dead temporarily) then, believe me, I will do it.

The best thing about the length of my original post is that I had no idea I was making it that long. Woo!

I'm not sure where my concern for the ohm values of the bus speed resistors comes from. I'm not adding any - only removing. In any case, it could be fun to know.

So, I guess this weekend I'll look into ordering fans, head over to Radioshack and grab a few things.

Oh! There is one question I haven't been able to answer through continued research:
Q: Can the copper heatsink be installed in first gen MDDs (pre-FW800)? If so, that'll help a lot for cooling (especially with a pair of fans on top).

EDIT: After re-reading some articles, I've noticed two odd things. Verax fans are VERY hard to find in the US, and 65mm fans also seem to be hard to find. Hmm... Any insight, anyone?
Posted by: johnsawyercjs

Re: Big Plans for an MDD - Help Appreciated - 11/13/06 08:17 PM

Good deals on the ATI Radeon 9800 Pro Mac Edition can often be had on eBay for just under or just over $200.

Some people find that adding a USB card to most Macs will prevent them from going into deep sleep mode, if there's a storage device attached, whose icon is still mounted on the desktop, or some other types of USB devices--see the website.
Posted by: waamatt

Re: Big Plans for an MDD - Help Appreciated - 11/14/06 08:20 AM

Thanks for the info Johnsawyercjs. I got a PC Radeon 9800 Pro (256MB) off of Newegg for just under $100. I don't have any sort of USB cards. In fact, I have no PCI cards in my machine!

The sleep problem I have did not develop post-mod, it actually started happening after (if I'm not mistaken) the 10.4.7 update.

I did recently discover a few fun things: A few weeks ago I learned that my FireWire ports appear to be dead and the other day I learned that with my DVD burner in the lower bay set on Cable Select and hooked up to the ATA ribbon's lower/slave connection, I can't eject CDs if they've been in the computer for too long. How odd is that?!

I'm hoping that this weekend I can find the time to set the machine back to 867/133 to see if everything begins working normally again. If I can figure out the extra fan-speed controlling wire on this 120mm fan I bought works, I can also make this thing SUPER quiet. I bought a Thermaltake Thunderblade fan and it's made a HUGE difference over the weird Arctic Cooling 120mm fan I had before. Plus, since it has blue LEDs, my slot fan(s) have weird UV LEDs, and my fan controller has blue LEDs, the entire case lights up blue inside and it spills out various holes and seems and makes it real fun to look at. Especially where the speaker used to be. Even the handle to open the case has light coming out of it (there are two holes behind the handle).

So, at this rate... I should have a mod article by the end of the year, detailing the trial and error process of getting it to run faster... Or, as it turns out, not getting it to run faster. Oh, well! : )
Posted by: Waragainstsleep

Re: Big Plans for an MDD - Help Appreciated - 11/15/06 02:23 PM

I never use cable select except on certain G4 iMacs when they misbehave. Set it to Master or slave as appropriate. Might fix your eject issue.
Posted by: waamatt

Re: Big Plans for an MDD - Help Appreciated - 11/15/06 05:53 PM

Can it be slave if it's the only optical drive present? It was on Cable Select when I got the computer!
Posted by: Waragainstsleep

Re: Big Plans for an MDD - Help Appreciated - 11/16/06 11:39 AM

No, I think it needs to have a master to be a proper slave. If its on the end of a cable it should be set to master anyway.