MDD Mania (the Wind Tunnel Express)

The VMM grows in fits and spurts. Nothing happens for a while, then a bunch of donations occur or a particular model hits the point of “no commercial value” and becomes available in bulk on craigslist or at the local flea market. The PowerMac G4 MDD tower, aka the “Wind Tunnel” Mac, appears to have reached this point.

PowerMacG4-MDDThe PowerMac G4 MDD (Mirrored Drive Doors) was the final iteration of the very successful PowerMac G4 line. Sold in single and dual processor configurations, these were the last Macs which could be dual booted into Mac OS 9 and OS X; newer G4 models and all G5s run OS X only. With 4 hard drive bays, 2 optical drive bays, 4 PCI slots and up to 2GB of RAM capacity, the MDD was Apple’s most expandable Macintosh on the market since the PowerMac 9600.

The MDD tends to run hot, and was the first Apple desktop with variable speed fans. A low whirring sound is always audible, and with fans going full blast the press quickly bestowed the moniker Wind Tunnel Mac. This (acoustic) feature lived on in the even-hotter G5 iMacs and PowerMacs.

I’ve been planning to add a Wind Tunnel to the collection for some time, but until recently the dual-proc models were still selling for several hundred dollars each and I didn’t have a major need. However last week one belonging to a client of mine had a power supply failure, and she decided to upgrade to a new Mac Mini. After assisting her with the setup and data migration, the MDD was donated to the VMM.

Two days later I was browsing my local craigslist and saw an ad for 12 MDD towers (all Dual Proc 1.25GHz) for $700! Turned out to be a batch pulled from a school and being sold via a commercial recycler. I didn’t need a dozen but picked up a pair for $150, and drove up to a warehouse on a rainy Monday afternoon to haul them home. These two models turned out to have some minor problems of their own – each was missing a USB and/or FireWire port – but otherwise they both worked fine.

The next day was the Parts Swap Learning Experience. I used the most cosmetically challenged tower as the sacrificial model. With help from a service manual and some creative tugging (but not breaking) I actually got everything out, and didn’t suffer any cuts or bruises. The cables for the power supply and speaker are definitely not the easiest things to manage, but reinstalling needed parts into the other towers went smoothly.

Still better than servicing a Mac Mini…

And just like that – last week I had no Wind Tunnels, and suddenly I have two with spare parts. I migrated the Vintage Mac Museum website to the new tower, and in the process upgraded from Panther Server 10.3.9 to Tiger Server 10.4.11 – yahoo! The “new” system does actually feel a bit faster, and it’s definitely a few decibels louder than the Graphite G4 tower it replaced.

A Mac Mini Server may come soon, but I’m glad this old friend has finally arrived in the VMM.

One response to “MDD Mania (the Wind Tunnel Express)”

  1. Adam Rosen says:


    Anonymous said…
    Hi! I am just retiring my G4 MDD due to a spent PSU and was googling looking to see if there’s value in any of the parts… Your blog popped up and you seem to be quite knowledgeable on these things. Do you have a sense of worth of any parts for this unit to sell or do you think I should just recycle it? I don’t know how to get back here to this site to check out your reply, so please email me: Thanks! LJ
    June 16, 2010 at 1:43 PM

    Anonymous said…
    1.SLEEP ISSUES: It takes a good 20secs for new HDD Drive (7200speed)&500Gig to do anything from a sleep awakening. I mean, it’ll open Mail window asap but to access mail or anything which triggers the HDD–takes 19-20secs! I have tried PMU reset and PRAM resets, dumping some “ByHosts” (read this somewhere) and all out of remedies….(sorry if not the same thread)

    2. NOISE: My Dual MacPro G4 MDD is so noisy (I missed the Apple Fix years ago and it’s too expensive I feel to replace the fans—anyother fix ala software or some utility fix? (sorry if not the same thread)
    July 20, 2010 at 2:51 PM

    Adam Rosen said…
    If you set the hard drives to Never Spin Down in the Energy Saver System Preference, that may help with performance.
    July 20, 2010 at 11:51 PM

    Anonymous said…
    I love my G4 MDD, though it sure is loud. I’m just getting ready to set it up as an Apache web server so that I can get a bit of a feel for how difficult it would be to set up a truly vintage machine (probably a Performa 638CD, but that may change due to the fact that the server has to run all the time and it is LOUD) as a web server. I know Apache will probably be easier, but I still want to give it a try. I might post a link here soon.
    November 29, 2010 at 10:47 PM

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