MDD Mod Status Part 2 - problems persist

Posted by: waamatt

MDD Mod Status Part 2 - problems persist - 09/15/06 08:28 PM

Hey, everyone. My modded MDD continues to give me problems. I tried different RAM (just one 512MB PC2700 stick), a different ribbon cable for the HDD (which is back on the ATA100 bus), removing the extra fans, and checking to make sure all hardware was securely attached.

I can get the system to boot no problem, but once I start doing anything, including doing nothing, it just freezes up. I get a spinning beach ball that never goes away.

Noting that Temperature Monitor never seems to show my CPUs even getting to 50C, I doubt it's a heat issue. I did notice that the power supply was not entirely, 100% connected to the mobo, so I made sure it was clicked into place. I took out the case speaker as it's pretty useless.

The only things I can think at this point are any one or combination of the following:
1. In removing the two resistors to bring the bus speed from 133MHz to 167MHz, something else got damaged, such as another resistor.
2. Building off of #1, the two resistors aren't truly removed, even though I held one in my hand after taking it off. The other either got lost or was destroyed by the soldering iron. Either way, my dad I made sure the spot it was on was clean enough to truly bypass whatever was left. Or did we?!  ::)
3. The processors are not stable at 1.08GHz. This would require down-clocking them back to 867MHz, which would probably require buying resistors (I need to check XLR8YourMac for the article with the different configs).
4. The processors need more voltage at 1.08GHz. Maybe?
5. I need to reinstall OS X. (I backed up the system already, but have since made a change or to, and I'd be slightly sad to lose the beta versions of Temperature Monitor I've been getting.) This would be possinble, assuming the system can stay running enough to do it. Booting off of a CD seems to work A-OK, though I haven't left it running for extended periods of time. I tried to reinstall OS X off of a 10.4.3 DVD that I know works, but it failed. It never even started the reinstall because the hard drive was exactly as it was before the failure. Fun fact: Running Disk Utility after it told me to Restart and try again got me the Spinning Beach Ball of Death, which eventually went away to reveal an inability to restart. The DVD would spin up for a while, spin down and sit for a bit, then spin up again. I eventually just held down the power button.
6. Oh, and there's the whole 80mm fan having a higher amp usage?/rating? than the one that was already in the case, which is why it's not hooked up to the mobo but is instead on one of the 12V leads

I'd have something to say about the sleep capabilities of the system if I had anything positive to say about the rest of the system.

On the bright side, both the iMac (now an MDD) and the Modded MDD are backed up and the un-modded MDD runs great.

So, I think the modded MDD's PSU has a total output of 360W (what an odd number), while the unmodded MDD's PSU has a total output (for sure, since it's not all in Chinese) of 400W.

If I didn't already say it, the system is pretty damn quiet without the extra two fans. The loudest component is the hard drive when it's reading/writing.

I have yet to report my problems to other sites, like the Apple discussion center.

The fan controllr I bought fits in the 5.25" chasis, but does not fit in the case. D'oh! I can either massacre my case to make it fit, massacre the controller, or massacre the chasis (which is, in my mind, the best option). That, or I can eat the $13 (it'd be fun to keep the thing because of what it does) and buy a 3.5" bay controller and mount it on a 3.5"->5.25" adapter. At least that it'd probably not stick so far out the front of the optical drive chasis that the chasis itself won't fit.  frown

OK... If anyone has any adivce, I GREATLY appreciate it to no end. Thanks in advance.

Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/16/06 04:12 PM

Note on the unmodded Dual 867: It can't go to sleep properly either. I'll try re-installing Mac OS X. It's fourth RAM slot appears to be dead.

Progress has been made!!!

After trying to re-install OS X on the 200GB drive in the modded MDD for the second time, it failed at the Verify Disk process. I put the drive in the ATA66 slot like it was before I did all of this, and it re-installed just fine. Conclusion: There IS something wrong the ATA100 bus on this machine. I've used the same cable and jumper config on both busses.

I still have to get Mac OS X back up to 10.4.7 and put back all my third party stuff and the Dev tools, but I also need to put in the 2x1GB 2-3-2-5 PC3200 RAM and see if it causes any problems from about 15-20 minutes of general use.

If that's OK, then it's time to put the extra two fans on, even if I don't immediately hook them up to a fan controller because without them the CPUs are running HOT HOT HOT!!! After Mac OS X reinstalled the system rebooted, the CPUs were at 60.1C. Not good!
Posted by: maestro

Re: MDD Mod Status Part 2 - problems persist - 09/16/06 04:55 PM

Yep those cpus be hot! >:D  But that is within range for that model.  Apple's aesthetic got in the way of function with these models.  There a lot of thing you can do to cool it down.  I would start by swapping in an Apple copper heatsink.  Try, that is where I got mine.
Posted by: Waragainstsleep

Re: MDD Mod Status Part 2 - problems persist - 09/16/06 06:02 PM

If you have an Apple authorised repair centre anywhere nearby, I would ask them if they would stick it on test for you. They have diagnostic discs to put the hardware through its paces, this should show up any faults with the ATA controller. You won't necessarily be in the clear if it passes all tests, but you'll know  where the problem is if it fails.
Maybe you can persuade them to put it on test without charging you. I know some places will charge you just to look at it.
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/16/06 11:53 PM

maestro: I have a copper heatsink. I think I need to do look into the Apple Fan kernel extension mod. The extra two fans are on and I found a sweet spot to mount the fan controller. The ATA100 bays that nearly touch the heatsink have a hole where the chasis screws in to keep it from wriggling too much. I put a screw with a head that's bigger than the other screws and, once I secure it in with some duct tape, will have a perfectly functional controller. Even with the extra fans back (and not running too fast/loud) the temp gets high pretty fast, which worries me. Maybe repeatedly opening and closing the case and moving things around has weakened the heatsink's connection to the processors, or maybe Temperature Monitor is reporting incorrect values. I still have two 60x25 fans to put in the lower front of the case which I'll then rout over to the fan controller and have them just run super slow as a way to get the lower part of the case's airflow started.

The speaker has been removed to aid in keeping the upper case cool, if I didn't mention that earlier or in the other thread.

War, that's not a bad idea, but before I look into that, I'm going to focus on getting the system up and running. Plus, now that I have the fan controller where the ATA100-connected drive(s) would go, maybe I'll just settle for ATA66. It's never bothered me! Besides, this system might as well be a Mac Pro compared to my iMac DVse.

Fun times: The guy who sold me my second Dual 867 MDD threw in an old PowerBook G3 just to get rid of it. Time to think or tinker... Or thinker.

55.5C after not even ten minutes. Ran the Xcode installer off of a 10.4.3 DVD and am now running Software Update to get back to 10.4.7. Maybe I'll crank those rear fans up a tiny notch after the restart...
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/17/06 02:16 AM

OK... Update. Due to some silly things I did, the 120mm fan wasn't spinning. It is now, but the temperatures are still higher than before the whole "freak out" period that caused me to reinstall OS X. Even with the extra fans running at pretty high speeds. I wonder if the fan controller is giving off some absurd amount of heat, which it would then distribute across the top of the heatsink if it was. Ugh.

It'd be one thing if it shot up to 50-54C and stayed there, but when it continues to climb towards 60, I have to figure that something's not right!
Posted by: maestro

Re: MDD Mod Status Part 2 - problems persist - 09/17/06 03:11 PM

Those temps are normal for the stock case.  All the fans in the world will not do any good unless properly used.  What that case really needs is a better way to exhaust the air.  You could add an 80mm to the back of the case behind the cpus or two 60mm inside the back behind the cpus.  Venting near the pci slot area is key too.  Putting a blow hole in the top of the case is ideal but takes some care and complete disassembly.

I doubt the fan controller is subject.  The cpus, memory and vga card give off the most heat.  If you were to try that copper heatsink it would lower temps 2-3 C.

Check out my first MDD mod guide for some tips on easy cooling solutions.  Its called Really Cool G4 part 1.
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/18/06 05:57 PM

I have the copper heatsink and two 60mm fans behind the CPU already.

Oh, and the random hard freeze (kernel panic, I assume) is still happening but now it takes a lot longer. (Used to be 1-5 minutes.) It happened last night while I was looking up tutorials and guides for Wings3D in a version of WebKit from... Four days ago?

I WILL get to the bottom of this because I really don't want to have to bring this computer to any repair shops and pay some guy a bunch of money just to look at the insides and not actually do anything. <- Yes, that's a worst-case repair shop scenario.
Posted by: Kisin

Re: MDD Mod Status Part 2 - problems persist - 09/18/06 08:41 PM

congrats on your mod, it seems really complicated, it also seems like you're not sure of where the heat is being generated inside the case. I used to have an automotive multimeter which had an attachment to measure temps, you just touch the tip to the surface and it would give you an accurate temp reading, you could even use it for air and water/fluid temps. maybe if you can get a hold of one of this you could test the air/heat flow inside the case
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/18/06 09:17 PM

Good idea, kisin. I could probably stand to have one of those for the future anyway. I had to rely on my dad for a lot of the tools since I have pretty much nothing at my house. If something breaks (computer or otherwise), I'm sort of screwed. smile

I wouldn't say the mod itself was complicated. Finding and removing the resistors to go from 133MHz to 167MHz bus speed was a cinch. Now I think I'm going to drop the CPU speed (ie, the multiplier) to see if it'll help stability. Tigerclaw at the World of Warcraft Mac Support forum made an interesting point about the northbridge possibly not being able to handle these higher speeds. I'd be amazed if anyone from Apple responds to my thread on their support forums.
Posted by: maestro

Re: MDD Mod Status Part 2 - problems persist - 09/18/06 10:52 PM

Okay, I have found that a lot of time kernal panic syndrome is caused by memory.  Even if the test CD says its okay.  Try leaving just one in and rotating them to see if that helps.  I have had a couple of sleepless nights building macs from scratch and it always came down to the fact that the ram was bad or OSX just didnt like it.
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/20/06 04:13 PM

Let's see if today it will let me post... : )

I have a slew of PC2700 RAM from OWC and Crucial. While I can easily test all the sticks because of that (they're all 512MB, too!), it'll just be really time consuming. I think I'm also going to clock the CPUs down by changing the multiplier from 6.5x to 6x (you can even do 5.5x which in my case would result in something nutty like 919MHz).
Posted by: Waragainstsleep

Re: MDD Mod Status Part 2 - problems persist - 09/20/06 09:30 PM

How about this: Since you started with a dual 867 Right? You can boot OS 9. It doesn't even take that long to install if you don't have it already. If its still unstable in 9, then its probably your bus overclock which is causing the problem. If it runs OK, its a RAM issue. You can even download and run DIMM First Aid if you can still find it. This will test all your RAM at once. If its the bus, you can add a heatsink to the Memory controller to see if that helps. If its RAM, try some 3200 if you have it.
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/21/06 04:53 PM

Originally Posted By: "Waragainstsleep "

If its RAM, try some 3200 if you have it.

I have PC3200 in there right now. smile There's some guy on Apple's Discussion Center telling lots of people to never put PC3200 in an MDD. Then again, this same guy said you can't do a 2x1GB config, which I responded to by providing a link to the Developer notes for the first MDDs showing specifically that a 2x1GB config is A-OK.

Thanks for the advice, War. I tried to flash the 9800 recently and didn't realize I never actually flashed it so I thought I did it wrong, got all bummed, realized my mistake, and just tried to do it again, only to realize that my computer now refuses to boot with my PCI Nexus128 card in place. It doesn't matter which AGP (if any) I have in there. Oh, well. There's always that VNC method or paying $25 to have some guy do it (and solder on the 128K EEPROM I bought).

This weekend I'll try and mess with the RAM. Which chip is the memory controller? Is it the big square on to the left of the RAM slots? If it's on the underside of the mobo, I doubt there're any kinds of heatsinks I could add to it.

Now to go find a place that sells 1000 ohm resistors. Another guy from Apple's Discussion Center said I definitely need 1k ohm resistors, but that apparently 0 ohms or a dead short work too. I think I'll stick with the 1k ohm resistors to play it safe.
Posted by: Waragainstsleep

Re: MDD Mod Status Part 2 - problems persist - 09/21/06 06:49 PM

The memory controller looks a bit like the CPU. Should be marked MPC something or other. Most of the older ones had a shiny purple metal surface visible. It should be between the CPU and RAM slots. I'll look in mine next time I get up...

Attaching a heatsink may not be straightforward, but its worth a try. I would say run it with the door open and hold the heatsink on, but I don't know how hot it would get and many stock MDDs actually overheat when run for any length of time with the case open. Maybe if you pointed a big desk fan at it.......
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 09/21/06 07:29 PM

I don't see anything between the CPU and RAM slots. If it's there, it's under the CPU board. There's an Agere brand chip (pretty large) to the left of the CPU board, but I think that may be the Boot ROM chip since it says Apple on it.

OK... So, new info: The PC3200 Patriot memory I have is 2.7V when the MDDs have/had 2.5V slots. Could be a problem. Hard to say. The computer only crashes under heavier loads, so it's either unstable processors, overworked bus, or the RAM isn't friendly. Only way to tell? Crazy Photoshop routines, lots of 3D modelling, playing World of Warcraft (launching, logging in, and entering the world is no problem - it's moving around in the world that crashes it or the computer).

I found out that when I was out my wife used the computer for a lengthy period of time last night and it did not crash, but she wouldn't have been doing anything intensive.

Also, when looking for 1k Ohm SMD resistors on Mouser, I discovered it's not so simple... There's a +/- % tolerance, they have wattage ratings, temperature coefficients, packagings, and more. Guess that if I'm going to drop down to an even 1GHz (well, 1002MHz), it's going to take more research.
Posted by: Waragainstsleep

Re: MDD Mod Status Part 2 - problems persist - 09/21/06 10:30 PM

I can't see one on mine either. Got a sneaky suspicion its on the other side, using the metal of the case as a heat sink. Cooling that any further is going to be tricky.
Posted by: maestro

Re: MDD Mod Status Part 2 - problems persist - 10/16/06 08:36 PM

3200 ram runs fine in the mirrored doors.  I too have two 1gb 3200 sticks and it has been fine.  I think that you should change the bus back to 133.  I would not be surprised if that is causing your problems. 
Posted by: waamatt

Re: MDD Mod Status Part 2 - problems persist - 10/17/06 04:53 PM

Thanks for that info, maestro. I still have yet to try setting the CPUs to a lower clock speed. I can go as low as 913 or so MHz before there's no point in having changed the bus speed. Naturally, if none of that works, I'll be back to a 133MHz bus. What'll be interesting is trying to overclock the CPUs with the 133MHz bus speed and seeing if similar problems pop up.