Well I did say I was going to get another Mac Pro and lo and behold - here it is. I can also say with certainty that a fair number of you reading this are rolling your eyes at the mere sight of this thing. This of course, is the infamous Mac Pro 6,1 - widely regarded as one of the worst redesigns that Apple ever released - and I'm going to tear it apart.
Full disclosure, I actually briefly owned one of these computers for a short while back in 2017 and I even took the time to shit out a page of complete diarrhea in it's honor before chucking a bunch of new parts into it and selling it on eBay.
I didn't even properly benchmark the stupid thing. I just attempted to run a handful of Steam titles - most of which didn't even work properly or were castrated in some fashion compared to their Windows versions, and called it good. I mean, what the fuck, man?
Read that "review" for yourself if you want, but prepare to cringe.
 |
| What the actual hell are you talking about, you 18-year-old nincompoop? |
In fairness to myself; that was only the second Mac I've ever owned and my knowledge of PC hardware was still pitifully thin. I really had no concept of how severely limited the "Trashcan" was compared to it's predecessor, nor why it was so reviled amongst actual power users. I basically concluded; "Hey it looks cool! And it seems pretty powerful! Is it worth it? Uhhhhh..."
Now, almost eight years later, I’ve picked up another 6,1. My main reason? I need a replacement for my painfully slow base-spec 2014 Mac mini, which has been serving as my household Plex server for the past few years. Any flavor of 6,1 is frankly overkill for that job, but the extra CPU power will help with transcoding, and the additional RAM should make operating it headless less of a pain.
Since I was planning on running this machine 24/7 with more than one server container and multiple subsequent client connections operating on it at any given moment, I wanted to make sure it's weird-ass combined cooling solution was in peak working order.
Because my machine was manufactured in 2016, bordering on a decade old and likely hadn't been serviced since; that mainly boiled down to replacing the thermal paste on the CPU and both GPUs and possibly the thermal pads on the GPU memory modules if necessary.
But this is an extremely weird device, and taking it apart is quite unlike any other computer I've ever worked on. To gain access to the CPU, you have to take the entire computer apart. That's not an exaggeration: you literally have to tear this thing down to it's very core, even if it's just to do something as mundane as replacing thermal paste.
Imagine a normal desktop computer, but instead of just pulling four screws and yanking off the the CPU cooler to access the CPU, you have to first disassemble the entire case, remove the GPU and pull the GPU cooler off the GPU, remove the power supply, then remove the motherboard. Then and only then; you can finally remove the CPU cooler and access the CPU.
No wonder Apple couldn't figure out how to update the stupid thing - but it's not all bad.
Despite the shortcomings of it's design from a hardware scalability standpoint, The 6,1 Mac Pro is still one of the most user serviceable machines Apple ever released during the Tim Cook era. The entire machine can be taken apart with a screwdriver and each individual component can be serviced or replaced - though some parts like the logic board, power supply, SSD, and dual GPUs are proprietary and are generally harder to source and more expensive to replace than standard PC equivalents.
That said, the CPU and RAM are normal components and can be replaced with any parts that meet the machine's requirements. DDR3 RAM and Xeon E5 CPUs are pretty cheap these days and since I have to take the entire thing apart to access the CPU anyways, I figured I might as well upgrade it.
Having done all of this before on my prior machine in 2017, this was a fun trip down memory lane. If you have some prior experience digging around inside a computer, taking the "Trashcan" apart isn't really any more difficult - it's just more time consuming and awkward than it would be had this thing been envisioned by someone with more than half a brain.
Granted, the first step is very easy. Flip the lock on the back of the computer and the entire outer cover just slides right off the top. It's quite satisfying.
With the outer cover removed, I then had a very clear view of both GPUs, the RAM slots, and the SSD. Still, in order to pull those GPUs out, I had to free up access to the bottom riser cables obscured under the bottom cap. At the same time, I went ahead and pulled the top cap, which houses the fan and the Wi-Fi antenna - since this will need to be out of the way for the later steps.
Removing that reveals the "genius" of this computer's design: the thermal core. It's really just a big triangular heatsink with a vertically aligned fin stack and three copper cold plates attached to each side. While it's capable of handling the combined thermal output of both GPUs and the CPU under load, it was also the crux that completely killed any of Apple's attempts to give the machine much needed hardware updates over the course of it's six year lifespan.
It not really hard to see why that happened. Apple had to strike a delicate balance between size, airflow, and surface area to make this cooler work with the computer's most powerful hardware configuration - not to mention it also serves as the main structural member holding the entire thing together. It works, but they gave themselves zero headroom to iterate upon it.
 |
| These can go right to hell. |
But with those endcaps removed, the GPUs are clear to be removed. The big, fat riser connectors on the bottom are popped off with a spudger and then the two grounding screws are removed. That leaves the four screws securing the GPU and retention spring to the thermal core. Undo those, and the GPU comes loose.
Or... it should.
I'm not entirely sure what the point of these two-piece screws are. I believe they're supposed to behave captive, allowing the GPU and retention spring to be removed as one complete piece and making reinstalling them easier. They're also used in a similar fashion with the CPU. More often than not though? The screws thread themselves apart, and if even just one isn't removed in it's entirety, it can make separating the component from the thermal core a real pain in the ass.
 |
| A close up of the AMD FirePro D700 die. |
This seems to be a result of Apple using blue thread locker instead of something stronger to bond the two halves of the screw together, and it just isn't reliable. It's likely a deliberate design choice so the two halves can be removed if the board ever needs to be replaced, but still I distinctly remember having to use pilers to unthread these stupid things on the CPU side of my previous machine, because they didn't separate properly and prevented me from removing the CPU. They just suck.
But I managed to get these ones free without too much fuss. Underneath, the old thermal compound was predictably looking a bit on the crusty side, but the pads looked fine so I left those as is. I cleaned the old compound off the coldplate and GPU die with IPA.
Now the daughterboard needed to be removed. This part serves more or less the same purpose as the big backplane boards on the old "Cheese Grater" Mac Pro, with riser cables connecting to the power supply and GPUs and a expansion card-like slot that connects to the logic board. Two screws and it wiggles free with a little gentle persuasion
With almost everything stripped away from the thermal core, you really start to see there really isn't too much sorcery going on with this design. Everything is mostly familiar - just arranged in such a way to fit this bizarre form factor and cooling solution. It's a clever, albeit terribly limiting solution to a problem that never existed in the first place.
The power supply and rear I/O come free with the removal of another six grounding screws, exposing the most normal looking piece of this whole "Trashcan" shaped puzzle: the logic board. The four Torx screws secure the CPU retention spring to the heatsink much like the two GPUs. Pull those off, and comes free.
Finally, I had reached my target: the six-core Intel Xeon E5-1650v2. It's not a particularly impressive CPU by the standards of today but for my own use cases, it would have been perfectly serviceable. But I like to have fun, so I'm dropping this into it instead:
That is a twelve-core Xeon E5-2697v2, originally the top of the line option for the 6,1 Mac Pro, and what an insane upcharge did Apple originally charge for these. I believe the top spec machine equipped with these cost close to seven grand when new. Now you can just buy one and drop it into yours for less then $40. If you ignore the fact this thing gets utterly destroyed in rendering tests by even modern i5 class silicon - that's pretty cool!
With the CPU swapped out, I began buttoning the computer back up. I opted for Arctic MX-6 as my new thermal compound - having finally decided to stop using the ten year old tube of Silver 5 I still have like an idiot.
I honestly kind of hate this stuff. It seems to work fine thermally, having used it on a few other systems since I this rebuild, but it's much thicker than a normal formulation like MX-4 and spreads nowhere near as easily. Using the little spatula to cover the IHS and GPU dies with this paste was like spreading plaster. I'm not a fan.
The last thing I did was cram in 64 GB of 1866 MHz SK Hynix DDR3 RAM. You might be wondering; "Why 64 gigs? Doesn't this computer support 128 gigs of RAM?"
And technically, you're right. It does, with one big caveat: it utterly tanks the bus speed. Loading up 128 GB worth of RAM drops the the bus down to 1066 MHz - except for the twelve core E5-2697v2, in which it case it drops even further to 800 MHz. That's less than half of what you'd get with 64 GB. Hard pass.
I haven't run many tests on the rebuilt machine yet as I was planning on doing a more formal review of this machine, but honestly I decided it wasn't really worth the effort. It's cool, but you shouldn't buy one with any serious intent of using it these days. It's performs exactly like a system it's age would - which is especially embarrassing considering Apple sold the damn thing until 2019 without a single hardware revision. A classic Mac Pro is still more versatile, and a M1 or M2 mini will smoke this thing in terms of efficiency for roughly the same amount of money on the secondhand market.
Just some very basic observations; the CPU package idles at around 47 degrees Celsius with it peaking at 81 degrees under full load. In a multi-core Cinebench R23 test, the E5-2697v2 clocked a score of 8218, which is right in the ballpark for that chip. I didn't observe any abnormalities, though I found Apple's stock fan curve to be extremely weak. Cranking the fan speed up to the maximum in TG Pro shaved several degrees off my CPU package temperature, by upwards of 14 degrees in some cases. It's not even a remotely loud fan to begin with, so I wonder what Apple's excuse was here.
I would have ended my discussion about this computer here, but I'm actually moving in roughly two weeks from now and am going to be put in temporary housing for the next two months while I work on getting an actual place. Since I no longer own a laptop and my desktop is a complete pig, this is actually the smallest computer I have that I can fly with. While I'm going to be primarily using it for work and continuing to use it as a server, I may actually try to game on this thing.
We'll see how that goes, but for now this oddball machine is doing everything I hoped it would. It's a symbol of Cook-era Apple's worst impulses, but it's also more interesting in a way that a MacBook Pro with a shitty keyboard and a useless touch bar isn't. I'm glad I have another one.
Comments
Post a Comment