Based on some great threads here, I decided to give my mac pro 2010 a mid-life upgrade. Got a hex core on order and looking to up the ram. So, its currently a single quad core with 4 memory slots. I currently have 12 gig with 3 4 gig sticks. Thinking I'd like to go to 24 or 32 gig. Or go nuts and get 48 gig? In any case, to keep a reliable machine, just how compatible does the ram have to be? Anybody have favorite sources of good ram at good prices? I have purchased from one outfit who claims their ram is better because it has the metal heatsinks and a mac proprietary temperature sensor. I see on amazon, ram that is quite a bit less expensive, but appears to lack a heat sink and do doubt no temp sensor. I think this stuff is simply your bread and butter 1333 ECC ram harvested from retired servers, or NOS stuff laying around. I did a few forum searches and was not able to find any discussion of the relative merits of brands of ecc 1333 ram, so a new thread. Apologies if I missed the same. Another quick one: I am reading threads here and elsewhere regarding pcie ssd. If I install an ssd pcie card, format with guid fs and so forth, can it be bootable? Are there special apple requirements for such a card. I see OWC has some stuff along these lines, but wondering if there are less expensive options that work just as well. Don't want to pay the apple tax unless its required. I have an ssd boot drive now that is plugged into the regular sata drive bays using a physical adapter--maybe going pcie would not be a signifiant speed boost... Thanks.