Mac Pro 1,1 Processor Upgrade
Following the previous upgrades to my 2006 Mac Pro I finally decided to take the plunge and swap out the original dual core Xeon CPU’s for some quad core ones. A matched pair of Xeon 5355′s came up on Ebay at a sensible price and from a reputable seller so I snapped them up. The seller actually had four pairs for sale and they were sold pretty quickly so there is clearly still some demand for 5355′s.
Heatsinks Removed
There are a multitude of videos available on Youtube detailing the relatively simple procedure of removing the old Xeons and replacing them. All you need are the new processors, some good thermal paste, a couple of Phillips screwdrivers and a 3mm Allen/Hex key which needs to ideally be at least 6″ long. You’ll also need something to clean the old thermal paste off of the heat sinks, isopropyl alcohol is ideal, anything else risks leaving residue which will negatively impact on the heat transfer between CPU and heat sink. Optional extras are a can of compressed air for cleaning out any dust build up and an anti-static wrist strap.
I won’t go into the full procedure here as others have already documented it well. A couple of points I would make are firstly many who have performed the upgrade refer to issues removing the memory cage screws, I had no such problems but did use a small jeweller’s screwdriver which allowed vertical orientation and full purchase with the screw head.
Original Xeon 5150′s
Secondly, I was surprised by how thick the factory application of thermal compound was when I removed the heat sinks, I had expected a thin veneer but it was definitely thicker than that. This rather threw me as to how much compound I should apply on re-installation.
In the end I decided to apply a thin line horizontally across the CPU’s with an additional smaller vertical line making a cross. I didn’t spread out the compound but instead allowed the pressure of re-attaching the heat sink to flatten it out.
Reassembly was straightforward, I even managed to complete the whole operation without dropping one screw. The machine promptly booted up and I ran Geekbench to assess what performance improvement the new Xeons were giving.
Geekbench Score Shows Huge Improvement
With the original Xeon 5150′s Geekbench would typical return a score in the low 5000′s. With the 5355′s the score has leapt to 9456, a very useful improvement in performance bringing my 2006 Mac Pro within touching distance of a 2012 iMac Core i7.
The only thing left to do now is monitor the CPU temperatures for a while to ensure the thermal compound is working well. There are a number of different apps out there that claim to give accurate read outs of the Pro’s thermal sensors, however in my experience they all seem to give different results. I’ve therefore decided to trust the software that I’m familiar with, namely Marcel Bresink’s aptly named ‘Temperature Monitor”.
Temperature Monitor
This is showing the cores running at an average of about 40°C under light load* which is around 30% higher than the previous processors. Considering there are twice as many cores and that the thermal compound has not broken in yet this seems pretty reasonable to me. Also a considerable upswing in the ambient temperature that has coincided with the upgrade must be taken into account.
I decided to download SMC Fan Control and crank the systems fans up by a couple of hundred RPM just to be on the safe side, they are still whisper quiet. There is one last issue that needed resolving, when you perform this upgrade and click on About This Mac you’re likely to get a processor unknown reading although System Report will show the correct number of cores. There are a couple of solutions to this, you can try upgrading the 1,1 firmware to 2,1 using this utility. Or you can do what I did which was download the CPU injector Kext from here and install it with a kext utility, I used Kext Helper b7 here.
*After three months of running smoothly the CPU temperatures under light load are now averaging around 32°C so clearly the thermal compound has bedded in well and I’ve been able to leave the fans running at factory settings. I recently installed Windows 7 and have been enjoying a number of games, the machine remains stable and reliable.
Very cool post. Just got my hands on a 1,1 Mac Pro for $350. Ordered my processors and will do the swap when they arrive. Was there a particular guide that you found helpful when doing yours?
Not a specific one Ryan, there are a few videos on Youtube which are helpful. I think I looked at a number of videos and blog entries and sort of aggregated everyone’s experiences/advice. It is pretty straightforward as long as you are methodical and careful.
Nice price on the 1,1, you’re going to have quite a machine for not a lot of dosh!
Yeah, I’m pretty stoked about it. I’m hoping to have a pretty decent system for about $600.