Upgrading and Analyzing Apple's Nehalem Mac Pro
by Anand Lal Shimpi on July 13, 2009 5:00 PM EST- Posted in
- Mac
The two heatsinks on the Mac Pro aren’t interchangeable, so keep track of which one came from where and don’t try to force their installation if they don’t fit properly.
After we completed the swap, we powered the machine on and were met with the worst sound: fans that didn’t spin down. The Mac Pro refused to POST and forcing it to turn off revealed a CPU A Temperature Overheat warning LED on the motherboard.
Removing the CPU_A heatsink revealed the problem:
uh-oh
CPU_B was fine, but CPU_A was far from it. While there are no pins to bend/break on these LGA CPUs, if anything goes wrong the socket is toast. In this case, both the socket and CPU were beyond saving.
To date I’m not sure what went wrong, but I have two theories. Unlike desktop Nehalem motherboards, there is no clamp that holds the CPU in place. There’s a chance that during the heatsink installation that the CPU moved slightly and shorted as soon as it got power.
The other theory is that I somehow over tightened the heatsink on CPU_A. Remember, the chips I used had heat spreaders, the ones they were replacing did not. The added thickness of the heat spreader could have helped push the CPU too hard against the pins in the socket, causing some of them to move out of place.
Regardless of the how, what remained was that I now had a dead Xeon and a dead Mac Pro processor board on my hands. The CPU I could always replace from my stash, but I don’t keep many Nehalem Mac Pro processor boards in my parts closet. This would require a trip to the Apple store.
And if you’ve ever walked into an Apple store holding a Nehalem Mac Pro processor board, you’ll get some looks.
Thankfully, the folks at the Crabtree Valley Mall Apple Store in Raleigh, NC are AnandTech readers and quickly understood what had happened. They ordered the replacement part and I waited. If you’re curious, it’ll cost a bit under $400 to replace the processor board in an 8-core Mac Pro provided you allow Apple to keep your dead board.
The new board and its accessories
It’s been years since I’ve killed a processor and this would be my first LGA socket death, so I was admittedly nervous once I had the new board in hand. I went in and tried to replace the chips again, this time under tightening all of the hex screws on the heatsinks just to be safe.
I mounted and dismounted each heatsink three times before committing to the install. Nervously, I hit the power button.
I had good news and bad news.
The bad news, the fans were spinning at full speed. The good news? The upgrade worked. Initially I didn’t tighten the heatsinks enough so some of the memory channels weren’t working, but a couple more spins of the hex key and I was in business.
The fans spinning at full speed were caused by the thermal sensor on one of the heatsinks being dead. It looks like it died when the first CPU shorted out. The folks at the Apple store had to order me a replacement heatsink as well.
After the smoke cleared and my embarrassment subsided, I had an upgraded Nehalem Mac Pro.
I started with a pair of 2.26GHz Xeon E5520s and ended up with a pair of 2.93GHz Xeon X5570s.
Gaining access to the processors is far easier than the previous generation Mac Pro, but you have to exhibit more care in physically replacing them. The fact that the CPUs I used had integrated heat spreaders hasn’t caused any problems either. Temperatures are well within reasonable limits, the fans are just as quiet as before and Turbo mode still works.
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jamesst - Tuesday, July 14, 2009 - link
"The Lexar reader is FireWire 800 (woo!) and the iSight is FireWire 400; I can’t use the iSight on the new Mac Pro."You can still use your Firewire 400 iSight camera on the Mac Pro's Firewire 800 ports. All you need is a Firewire 400 to Firewire 800 cable. I know that Belkin makes just such a cable and I even purchased one at my local Apple Store here in Raleigh, NC.
joelypolly - Monday, July 13, 2009 - link
I have actually had something similar happen to a socket I was working on. It was a matter of finding a sewing needle and moving each "pin" back to the original position.HilbertSpace - Monday, July 13, 2009 - link
It would be interesting to try swapping the 2-socket tray with a 1-socket Mac Pro, and see if it works(?) Would be cheaper to buy the 2-socket board and upgrade yourself, no?MonkeyPaw - Monday, July 13, 2009 - link
Are FB-DIMMs going to disappear from the market? While at first it doesn't sound Mac-related, original MacPro owners might soon be running out of memory upgrade options (though I doubt they've held out this long to upgrade). It wasn't cheap to start with, but it seems like it was Band-Aid technology. The IMC was the answer, but FB-DIMMs were a stop-gap until Nehalem-Xeons could arrive. Perhaps a memorial article for the technology is needed?JimmiG - Monday, July 13, 2009 - link
Ok so I get it, even the "cheap" Mac Pro uses a Xeon, not an i7... But for all intents and purposes, it's an i7 920.Who in their right mind would pay $2,500 for a i7 920 system with 3GB of RAM, 640GB HDD and a rebranded Geforce 9500 GT? You can build a similar PC (or hackintosh) with the same specifications for the a fraction of the price - in fact you could also bump the RAM to 6GB and throw in a 1TB drive and a 4870 1GB or 4890 if you wanted and still stay *well* below that price point, even if using quality components and case.
The Mac Pro isn't even shiny!
plonk420 - Tuesday, July 14, 2009 - link
did you read page 10?MrDiSante - Thursday, July 16, 2009 - link
Did you read his comment?ltcommanderdata - Monday, July 13, 2009 - link
Another great in depth review. Your experiences with upgrading the processors were particularly interesting although I don't think it'd be something I would try.I just wanted to suggest you Boot Camp the Mac Pro and run the benchmarks needed to add 2x2.26GHz Gainestown and 2x2.93GHz Gainestown results to the Anandtech Bench. It might also be interesting to get a sample of the new nVidia GTX285 Mac Edition. It would certainly address the 1GB of VRAM concerns and would be cheaper than getting the HD4870 if you need 2 dual-link DVI ports since you don't need to buy that finicky adapter. There really aught to be DVI to mini-DP adapters though for people who still want to use the 24" LED display.
http://www.glbenchmark.com/result.jsp">http://www.glbenchmark.com/result.jsp
Oh and for interest, there turns out to be a 3D benchmark comparing the various iPhones to other cell phones. It's called GLBenchmark and needless to say, the iPhone 3G S is a screamer. They are also detecting the iPhone 3G S GPU as a PowerVR SGX 535.
ddobrigk - Monday, July 13, 2009 - link
Actually, the Nehalem-EX's octo-core possibility is a no-go for now. It is a future product and has not been launched yet.Also, a little bit of nitpicking, but it won't use LGA1366 like these Xeons, it'll use LGA1567, because each CPU will sport a 4-channel memory controller.
In addition, it'll sport 4 QPI links, and its intended target are 4-way and 8-way systems, not really 2-way systems. A few rumors exist about some integrators being interested in 2-socket systems, though we're still a few months from actually seeing any LGA1567 motherboard on display, AFAIK. All we saw was an Intel Demo about it.
Don't know if Apple intends to go with 2-socket nehalem-exs, anyway, because when Nehalem-EX really hits the market, there'll also be the 6-core westmeres, I think. In any case, we're way beyond a reasonable number of cores for the typical user. :D
BrianMCan - Friday, July 17, 2009 - link
MacPro's really aren't meant for typical users ;)Scientific, Video/Movies, 3D, and advanced users who may do many things including the already mentioned, or many things at once. Always other things I can be doing while some video is rendering, including playing some Civ 4, or starting the next video project, researching upgrades & repairs for customers, stuff like that.
Although I personally may wait for the 2nd gen Nehalem MacPro's before I upgrade from my first gen MacPro, other than raw processing power, it does most of what I need efficiently enough.