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macbook pro mid 2009 support 1333 mhz?
- Thread starter selcuks
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I just installed 8GB of 1333MHZ memory in my late 2008 Macbook. Everything is running perfectly. It even feels a little faster as well.
I tried both Corsair CMS08GX3M2A1333C9 and Crucial CT51264BC1339, both of which are 1333MHz memory. I ended up returning the Corsair memory because I ended up finding the Crucial memory $35 cheaper the next day. Both worked equally well and they both are top tier manufacturers of memory. I'd use what ever ended up cheaper.
Matt
I tried both Corsair CMS08GX3M2A1333C9 and Crucial CT51264BC1339, both of which are 1333MHz memory. I ended up returning the Corsair memory because I ended up finding the Crucial memory $35 cheaper the next day. Both worked equally well and they both are top tier manufacturers of memory. I'd use what ever ended up cheaper.
Matt
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It might support 1333mhz (don't quote me on that), but the reason that 1066mhz is there is for that 1:1 FSB:RAM ratio which is the most stable.
The 1333 Mhz RAM will work in a machine that originally had 1066 Mhz RAM, but will be clocked down to 1066 speed.
Yeah I know what you mean. As far as my experience though; I've had no issues of reliability or performance. I've run the long diagnostic test from the Snow Leopard DVD and it passed with no issues. I've also loaded the computer down and used all 8GB at once and I had not one issue with lockup's, kernel panic's, or performance.
The 1333MHz as proven to be nothing but reliable and one of the better upgrades that I've done to my computer.
Matt
Is there a way that I can test my system to see what the actual clock speed that my memory is running at? When I look at System Profiler it shows that 1333MHZ memory is installed. I assume it says that because it's reading the spec from the memory?
Matt
Ditto
I'm running the same 8GB Corsair package referenced below in my late-2008 MBP (2.53Ghz) and it seems to work fine. This RAM was originally for an i5 system, but I just read the story at 9to5mac about late-2008 MBPs supporting a full 8GB up from 6GB and had to try it out.
As noted, the system should clock it down to 1066 Mhz. It's passed a TechTools memory test without issue, so I don't expect any stability issues.
I'm running the same 8GB Corsair package referenced below in my late-2008 MBP (2.53Ghz) and it seems to work fine. This RAM was originally for an i5 system, but I just read the story at 9to5mac about late-2008 MBPs supporting a full 8GB up from 6GB and had to try it out.
As noted, the system should clock it down to 1066 Mhz. It's passed a TechTools memory test without issue, so I don't expect any stability issues.
I'm running the same 8GB Corsair package referenced below in my late-2008 MBP (2.53Ghz) and it seems to work fine. This RAM was originally for an i5 system, but I just read the story at 9to5mac about late-2008 MBPs supporting a full 8GB up from 6GB and had to try it out.
As noted, the system should clock it down to 1066 Mhz. It's passed a TechTools memory test without issue, so I don't expect any stability issues.
I actually disagree, but I can't find documentation that supports it. But I don't think it does get clocked down to 1066 Mhz. I think the board supports higher speeds. I have a mid 2009 macbook that i just put 4 GB of 1333 hynix ram in it, replacing the existing 4 GB of 1066. The OS reports 1333 vs 1066, which means that the bus definitely recognizes that it's running faster, and so does the OS. If the logic board dialed it down to 1066, the OS would not report 1333, it would report 1066, wouldn't it?
To back that, I did see speed increases in logging in, application loading, and boot times. If RAM configuration remains constant, and the amount of ram stays constant (and really the amount of ram does not impact speed in all cases), then the variable here is that the bus can handle 1333.
As a side note, many people think the amount of RAM matters for speed, and this isn't really the case. I'll use a pipe metaphor to explain. If you have a 4 inch pipe that is 1 foot long, you can push X amount of water through it at Y rate. If you have a 4 inch pipe that is 2 foot long, you can put 2X amount of water in it, but it still only passes through at a Y rate. More RAM means you have the ability to open more things at the same time. If you are using up all your RAM, then more RAM would absolutely speed up your system, if you are not, then more RAM will not have an impact, keeping all other variables constant.
Now, you change the speed of the RAM, which would be the equivalent of increasing the size of hte pipe, this allows you to transfer water at a faster rate. Again, the same pipe metaphor doubling the pipe size from 4 inches to 8 inches, your rate doubles.
The same rule is true for electricity, or anything really, and it applies to RAM as well.
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If the RAM is not being down-clocked, does this mean that the CPU is being overclocked since SDRAM must run in sync with the CPU bus? If so, this will impact on overheating, battery life and longevity of the system.
The memory will run at the Bus speed. Any profile utility will report the spec installed.
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Unfortunately "reports" and "supports" don't definitively mean the same as "runs at" where RAM and data Buses are concerned.
Unless a proper memory access test is run I'de seriously doubt the bus is running at the higher speed. If it can then the machine would support faster memory in full and there would be no sensible marketing reason to say it is limited to the lower speed memory.
As you say, there are implications of running the bus faster so if those issues have been engineered to be dealt with (at some cost), there would be no reason to throw that away by not marketing it as such.
I don't think so, but I could be wrong, but it still runs at the same voltage, 1.5. If you OC RAM, than sure, because you have to slightly increase the voltage. More speed doesn't necessarily mean more heat in all cases.
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Why would my performance increase then? Sure this is subjective, but I have no reason to make it up. I'm just trying to find an absolute answer here. I agree that reports/supports aren't the same, but the documentation i've looked up doesn't say much about max speed, it mentions what type of ram it comes with and the max amount of ram you can install.
Yes, hard drive does impact speed, in nearly everything, but that variable remained constant (The hard drive wasn't changed), so it's impact would be ~the same before and after, since you're not changing the variable.
Just to be clear. I have a test macbook pro that had 4 GB of Hynix 8500s (1066 mhz) ram. I have used it for a while, probably 1.5 years, so I'm use to the speed it operates at. I was given 4 GB of Hynix 10600 (1333 mhz) ram. The *only* change that was made, was a ram swap. The OS reported 1066 before, and now it reports 1333. Additionally, the machine is more responsive in literally everything I've done.
The research I've done isn't clear on the max speed supported. Take for example: http://support.apple.com/kb/sp541 where it says "2GB (two 1GB SO-DIMMs) or 4GB (two 2GB SO-DIMMs) of 1066MHz DDR3 memory; two SO-DIMM slots support up to 8GB". This tells us what RAM the machine comes with, and tells us it can support a maximum of 8 gigs. It doesn't tell us the limit though.
So I decided to contact Apple, as it seems most people are up in the air. They didn't have a clear answer as to why the OS was reporting higher speeds, as they mentioned that it should downclock to 1066. Quote from Apple:
"it is not supposed to be capable of running faster than 1066MHz. Even if you put faster memory in there, it would be limited to what the machine was built to run. Since you have put 1333MHz in there and it's running at that speed, I'd say you are benefiting from a fluke."
Yep... if the memory works at 1333Mhz at a 1066 system bus, then you are overclocking the CPU since it will have to work faster to deal with the bus speed increase. RAM and CPU work synchronized one with the other. I'm not a computer engineer, but if it wasn't the case, the communication between the CPU and RAM would be a mess. There are years since I took computer architecture classes, but I think the basic principles still applies to modern hardware. Also, DDR3 SD-RAM means that RAM works synchronized with the system bus.
Is the 1333 not just being read from the firmware chip on the ram module and it is just reporting what is installed?
I have read in one thread that as ram ages it gets slower. So maybe the new ram is running at the full speed of 1066 where the old ram had slowed down and that is the speed difference that you see!
Barney
I have read in one thread that as ram ages it gets slower. So maybe the new ram is running at the full speed of 1066 where the old ram had slowed down and that is the speed difference that you see!
Barney
The instantaneous load/throughput on the hard drive interface is what will throttle the RAMs ability to take data from the drive. Simply "not changing the drive" isn't enough of a constant. You would have to be reading the same files, in the same order with the same overlaps etc etc - and that can change between boot sequences....