When I tried to boot my Mac Pro recently, it failed -- all I got was a black screen and a chime. I opened the case, and on the motherboard, I saw two LEDs were red: the cpuA and cpuB failure lights.
My warranty is over, but here are the steps I followed to get it working again:
Turn off your Mac and unplug the power cord.
Remove the CMOS battery on the motherboard (just above the graphic card).
Wait 10 seconds -- I'm not sure if this is necessary, but it worked for me.
Plug the power cord back into the Mac.
Press the power button. The Mac should boot normally and give you the startup chime, but you want your CMOS battery back.
Turn off the Mac, then unplug the power cord again.
Put the CMOS battery back in.
That's it; boot and enjoy!
[robg adds: I've never seen this on my Mac Pro, and I'm not sure if it's a sign of a failing CMOS battery, or something else. I'm publishing the hint because (a) it may help someone in the same situation, and (b) to see if anyone has any idea of what may be behind an apparent failure of both CPUs. Please comment if you have any thoughts.]
I've been swapping hard drives in my Mac Pro a lot lately, and they kept getting more and more difficult to pull out once they'd been soundly seated, to the point where I was in danger of bending the lip of the sled.
I was about to experiment with lubricating the things with a little graphite or similar, when I discovered that they slide out much more easily if you reach both hands inside the Mac and pull gently and evenly on the far edge of the drive itself.
Need an extra MacPro hard drive sled for swapping secondary hard drives? If you do not need to swap out your primary hard drive, take it off of the sled and carefully install it permanently into the first slot without the sled. First put some thick felt on top of the grey fan box. The hard drive is supported by the grey box and felt perfectly solid in this setup. Now you have a free hard drive sled to swap drives in the other three slots -- this is better than pay $29 plus shipping.
[robg adds: While I do have a Mac Pro, I'm not going to test this hint ... I don't swap drives often enough to merit a spare sled. Looking at the interior of the machine, though, it looks as though it would work fine -- though clearly it's not the recommended drive mounting method. Proceed at your own risk...]
When I upgraded the video card on my Dual 1.8ghz PowerMac G5, I started having many difficulties, including:
Optical drive not recognized.
Video card fails to power display.
Hard drive(s) not recognized.
After several frustrating days, the solution was to reset the PMU on the motherboard. I suspect that on a newer G5, resetting the SMU would have the same effect. So, if you're out there having a hard time upgrading your G5, give it a shot!
[robg adds: I can't confirm this one -- if anyone has had a similar experience, please post.]
Apple's Intel Mac Mini has only one display connection, the DVI interface. In case someone has chosen a wrong display resolution for a connected display, it is very difficult to switch back to a usable resolution.
When (for example) using a Benq LCD connected via a VGA to DVI adaptor to the Mac Mini and changing the frequency from 60Hz to 75Hz, the Mini will always remember the chosen resolution, even if a PRAM reset or complete hardware reset is done. So the screen still stays black, as 75Hz can't be shown although the Displays System Preferences pane offers this frequency. It doesn't matter if you are connecting another display to the interface and afterwards changing the resolution; the Mini keeps on switching back to the former one if the misbehaving display is re-connected.
In order to switch back to a usable resolution, you will have to remote control the Mini from another Mac using screen sharing, Apple Remote Desktop, VNC, or Timbuktu. Even though the Mini's screen will be black, the remote Mac will show a usable image. While remote-controlling the Mini, you have to change the resolution within the Displays System Preferences panel. After changing the resolution remotely, the display should jump back to a usable resolution.
[robg adds: Apple provides a potentially easier solution to the black screen problem: use safe boot mode. Thanks to queue user fds for pointing this out.]
Some G4 Mirrored Drive Door (MDD) systems have cooling systems that run loudly as the CPUs get hot, especially the model affectionately known at the "Windtunnel" G4s. On those systems, enabling nap mode brings the normal operating temperature down remarkably well, thereby quieting the fans. This was covered in this older hint.
The method is basically to install the last version of Apple's C.H.U.D. tools that allows Nap Mode on those machines, which is version 3.5.2 [21MB download]. That version still works with Leopard, although notably it misreports cache sizes. However, the old command line utility, and therefore the derived AppleScripts, that people have relied on until now to enable nap mode have broken.
So here is an Applescript I wrote that will enable nap mode again, even under Leopard:
If you order a BTO Mac Pro with two internal hard drives, you may want to make a note of this. To make a long story short: Before firing up a new Mac Pro configured with two internal hard drives to run the Migration Assistant, turn it on in Target Disk Mode and rename the empty second hard drive to something other than Macintosh HD. Now, the explanation:
I was setting up a new Mac Pro for a user at one of my clients, and attempted to migrate her from her existing Power Mac G5. The new machine was configured with two internal hard drives, 500GB each. I attempted to migrate her data from the initial Setup Assistant, and everything went smoothly until we got to the actual "Transferring Information" screen -- no time estimate ever appeared in the progress bar, and the drives were not making sounds that would indicate they were being accessed.
I ended up rebooting the new machine via the power button and choosing not to migrate data when the Setup Assistant ran the next time. I made a dummy account and then ran Migration Assistant manually. I noticed that both internal drives on the Mac Pro were named Macintosh HD, and guessed that may have confused Migration Assistant. After I renamed the second drive, the copy proceeded without any problems.
To verify that the identically-named internal drives were indeed the problem, I stopped the migration, set the machine back to out-of-box state (except for the internal drives having identical names), and tried migrating the data from the initial Setup Assistant, and it worked flawlessly. I submitted a bug report to Apple about this, but thought I'd spread the word to possibly save someone else some time figuring this out before it gets fixed by a future version of Migration Assistant.
I am in the process of creating the "ultimate" Mac mini-based home entertainment system. One issue with using a mini is the lack of dual-monitor support, which is a real hassle if the mini is attached to a projector -- turning on the projector to see the screen each time is expensive and time-consuming. Since the mini only has one video output, I came up with a way to effectively mirror the video to both the DVI projector and a DVI-input LCD monitor:
Buy a DVI "splitter" cable (I got mine on ebay). You want a two-female to one-male DVI-D splitter.
Plug the monitor into one fork of the splitter.
Take the cable from the projector, and break off pins 6 and 7 (pinout chart). This will disable the monitor sense function, and the mini won't "know" the projector is connected. Plug it into the other fork of the splitter.
Make sure the LCD monitor's resolution matches the projector's native resolution (you may need to use DisplayConfigX).
Now go watch your DVD. Note that if you don't modify the projector cable, this setup may work when both the LCD and projector are on, but as soon as one is turned off, the mini will blank the video output.
I have owned an awesome Apple Powermac G4 for about two years now. It's a Dual 1Ghz machine, which is commonly known as the Mirrored Drive Door (MDD) model due to its mirror finished optical drive doors. It has been a faithful servant so far for all sorts of stuff like video editing, music production, photos, web surfing, email and business duties, to name just a few.
I noticed when I first got it that it was a bit noisier than my old G4 533 Power Mac, but until my girlfriend's mother complained that it kept her awake all night, I didn't really take much notice of it. After that, though, it started to drive me crazy and I started a long campaign to quieten the thing down.
First thing I did was search Google for information on how to do it, and I found this page, which documents in detail how to replace the main 120mm cooling fan.
After trying one fan that just didn't cool the G4 well enough, I found (on FrozenCPU.com) a SilenX 120x120x38mm fan (18dBA; 90CFM) which is whisper quiet. It also cools the Mac just as well as the original Delta fan that came from Apple, only it's about 300% quieter. It made a big difference.
This is going to be ridiculously simple for many people, but hey, I made this mistake and even Apple Support couldn't figure it out. Plus, documentation at the present time for installing AirPort cards is designed for a replacement card, which misses a vital step.
Anyway, if you have a G5 and have installed an AirPort card yourself, you should know this: Strictly speaking, there are two antennas!
There's the small internal antenna which you must click into the top of the AirPort card inside the Mac -- this bit is well documented.
Your Mac originally came with a T-shaped object, which is the external AirPort antenna designed to overcome the metal casing of your Mac. Plug this into the AirPort port on the rear of the machine, and your range will increase from about 1m to ... well, much, much more. Go look in the box -- it's probably still there!
I hope this saves someone some time; I still can't believe that Apple Support didn't figure this out straight away.