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Memory Type: SDRAM, PC133, SDRAM (non-ECC)Maximum Memory: 1GB
Memory or DRAM is the "working" memory of the computer. It's used to store data for programs (sequences of instructions) on a temporary basis.
video - installing memory
(based on 1 review)
Reviewed by 1 customer
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from Fresno, CA
About Me Power user
Comments about Crucial 512MB Upgrade for a Apple PowerBook G4 800MHz System:
I'm mostly pleased with how easy to order and the Crucial Finder that matched my memory choice for me. So far, no crashes. Not sure about change in speed.
Bottom Line Yes, I would recommend this to a friend
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What is the difference between DDR3, DDR2, DDR, and SDRAM?
Single data rate (SDR) SDRAM is the older type of memory, commonly used in computers prior to 2002.Double data rate (DDR) SDRAM hit the mainstream computer market around 2002 and is a straightforward evolution from SDR SDRAM. The most significant difference between DDR and SDR is that DDR reads data on both the rising and falling edges of the clock signal, enabling a DDR memory module to transfer data twice as fast as an SDR memory module. The generation after DDR, called DDR2, began to appear in mid-2004. DDR2 is faster than DDR, delivering bandwidth of up to 8.5 GB per second. Frequently, DDR2 based systems can use memory installed in pairs to run in "dual channel mode" to increase memory throughput even further.The most recent generation of memory technology, DDR3, began to appear in systems in late 2007. DDR3 is the next evolutionary step beyond DDR2 and operates at lower voltages, which means it consumes less power, and it can transfer data at rates up to 12.8 GB per second. Your Mac supports only the memory generation that it first shipped with. You cannot mix and match SDRAM, DDR, DDR2, or DDR3 memory in a Mac. The different memory types don’t function together, they will not even fit in the same sockets.Because of this, you need to make sure that your upgrade is of the same memory generation as the memory that shipped with your Mac. The easiest way to find compatible memory is to look up your system in Crucial's Memory Advisor tool, that will list only compatible memory for your Mac.If you don't know the exact model of your Mac, the Crucial Mac Scanner will automatically detect your system configuration and give you a report on which upgrade is right for you.
How can I tell if my RAM is bad?
If you are having performance issues, software “hangs” or random crashes—we recommend you run a memory test. For the Mac OS, a popular tester is Rember, which can be found here:
Set Rember to test “All”, and check the box next to “Infinite” number of loops, and let the test run for at least half an hour. Since Rember is running from your desktop, it's important that you shut down all applications before you run the test. If you have any programs open, the test will be a lot less accurate.
If Rember finds errors with your RAM, you may need to replace it. To request an RMA, fill out the online request form, or contact Customer Service for your region.
How much memory do I need?
If your Mac is getting a little older, you may notice that it doesn’t run as fast as it used to. A memory upgrade from Crucial.com can give your Mac the boost it needs – for surprisingly little money.The amount of memory you need to optimize your computing performance depends on your computer model and what you use it. Overall, we recommend a minimum of 8GB of RAM for systems with the capacity. Learn more from these guidelines.
How do I know what to order?
If you aren't sure what Mac model you have or what kind of memory it takes, you can get your System Profile through the Apple menu. The profile will tell you what kind of memory and how much memory is in your system.
1. Open the Apple menu, and then select "About This Mac".
2. The "About This Mac" screen opens. Click the "More Info..." button.
3. The Hardware overview screen will open. Click on "Memory"
4. The Memory Slot screen will now apear and show your current memory configuration, what kind of memory is installed, and there will also be a link to memory upgrade instructions for your model.
If you want to make it really easy for yourself however, our Mac System Scanner will do all this work for you.Just download the tool and we’ll show you what memory you already have, and what memory upgrades are available.
You can also go through our Mac Memory Selector and manually pick out your system from menus, for a list of all compatible upgrades Crucial offers.
Both the Mac System Scanner and Mac Memory Selector can be found on our Mac Memory page.
Time to Tame your Mac!
Everything you need to know about Mac memory upgrades from Crucial.com
If your Mac is getting a little older, you may notice that it doesn’t run as fast as it used to. A memory upgrade from Crucial.com can give your Mac the boost it needs – for surprisingly little money. Crucial.com prices are considerably lower than buying direct from the manufacturer – and we sell only comparable, high-quality memory that’s guaranteed to work in your system if you use our online tools.
· What kind of memory do I need?
DDR2 and DDR3 are commonly used it today’s Mac systems. They are not compatible—so you need to upgrade with the same memory type. Here’s more.
· What’s the difference between DDR2 and DDR3?
· How much memory do I need?
The amount of memory you need to optimize your computing performance depends on your computer model and what you use it. Overall, we recommend a minimum of 8GB of RAM for systems with the capacity.
What about my new operation system?
Lion OS-X information
Learn more from these guidelines.
· How can I tell if my RAM is bad?
If your system is running slow, it’s likely the RAM. But it’s not a bad idea to rule out other issues first. If you are having performance issues, software “hangs” or random crashes—we recommend you run a Memtest. Read this MacLife article to learn how.
· Can I really install this myself? Yes, you can! Here’s how easy it is!
Find your memory with the Mac System Scanner
Take the guesswork out of finding compatible RAM for your Mac system. Our Mac System Scanner does the work for you. Just download the tool and we’ll show you what memory you already have, and what memory upgrades are available.
I tried to upgrade the RAM in my mid-2011 27" iMac. I followed OWC's awful advice to leave the computer plugged in to a grounded socket (to discharge static, supposedly). Now the computer doesn't turn on. No power, no fan, nothing. I tried every combination of new and old memory and every slot. Nothing. I fear that leaving the computer plugged in may have damaged something irreversibly. Maybe lost the PMU? Has anyone encountered this? Does anyone have any advice? I would really appreciate any help. Thanks!
Just recently I purchased 8gb (4gb x 2) 1066 MT/s of ram that was put into an Imac (late 2009) with 3.06 ghz . I am not using the iMac as much as I thought and am using my macbook pro (mid 2009) with 2.26 ghz and 2gb 1067 mhz of DDR3 memory more. I am thinking of moving the 8gb of ram from the iMac to my Macbook pro and putting the original 4gb of ram back into the iMac. Would this be safe to do, or would I better off buying 8gb of new ram to put in the macbook pro?
I just bought these modules (see photo) 2 kits of 16gb of RAM (2x8gb each). I wasn't sure what's the number I should look at since they're different on packaging and on the label in the memory module itself. I'm waiting to receive my brand new iMac 27 late 2013, will be upgrading to 32GB.
Can ANYONE PLEASE confirm these modules have been working flawlessly using 32gb?
Thanks for any info!
I have a 17inch late 2011, 2.4Ghz Intel quad core i-7 MacBook Pro with 2x2GB RAM.
When I search for 16GB RAM upgrade using manual search I get two diferent results for my Mac:
part no. CT 3327407 ( when I select model with clock speed )
part no. CT 3373673 ( when I select correct model but without clock speed and also when I run the scan my system option )
Why two different part numbers when I scan and manually select model with processor speed? How can I trust which one is correct?
It seems that you are selling 2 different part numbers for my Mac model as both have comments from buyers ( 3 and 5 respectively )