i7 with 1333mhz ram does it work? Answer is here!

[FlavioX]

1333MHz CL9 memory works as well

When I ordered my iMac i7 in November of last year I immediately ordered 8GB of OZC 1333MHz memory thinking I would have my iMac quickly.

When I got the memory sticks I noticed that is was CL 9-9-9-24 and after reading this thread I was a little concerned that it might not work.

I only received my iMac this week (after two and a halve months waiting!) so I could test the memory now.
I've installed it and ran memtest all night long and the iMac didn't freeze so I guess CL9 1333MHz also works in the iMac.

When I bought the RAM There were no 1333MHz CL7 sticks for sale. They might be easier to find now though.

My average Geekbench score (32 bit) is 8395.

 

[DoFoT9]

When I ordered my iMac i7 in November of last year I immediately ordered 8GB of OZC 1333MHz memory thinking I would have my iMac quickly.

When I got the memory sticks I noticed that is was CL 9-9-9-24 and after reading this thread I was a little concerned that it might not work.

I only received my iMac this week (after two and a halve months waiting!) so I could test the memory now.
I've installed it and ran memtest all night long and the iMac didn't freeze so I guess CL9 1333MHz also works in the iMac.

When I bought the RAM There were no 1333MHz CL7 sticks for sale. They might be easier to find now though.

My average Geekbench score (32 bit) is 8395.

interesting to know!

this would probably be the cheapest price i could find in australia! pretty expensive for cheap. crucial is $120US, roughly $136Aus - and i dont think they charge for postage! might just go with the crucial stuff

 

[TMRaven]

Any updates on the stability of the CAS 9 ram?

 

[DoFoT9]

Any updates on the stability of the CAS 9 ram?

i dont think it will ever work (stable wise)

 

[hundert]

CL6

anyone tried?

I don't even know if SODIMMs in CL6 exist.

 

[TMRaven]

I only know of one cas7 ddr3 1333 204pin ram, and it's from kingston. Asides that, there's a plethora of cas9 ddr3 1333 ram. It's a shame there's not enough reports on its stability with the new iMacs.

 

[hundert]

There is CL5 1066 from Kingston and OCZ

KHX1066C5S3K2/4G

OCZ3MX1066C54GK

I think the CL5 1066 brings more than CL7 1333. If it works is another question

 

[hundert]

There is CL5 1066 from Kingston and OCZ

KHX1066C5S3K2/4G

OCZ3MX1066C54GK

I think the CL5 1066 brings more than CL7 1333. If it works is another question

 

[TMRaven]

The latency difference between CL5 ddr3 1066 and cl7 ddr3 133 ram is like a 1 or so nanoseconds. What's more interesting is the theoretical 4gbps bandwidth that dual channel ddr3 1333 can provide vs the dual channel ddr3 1066. Gaming benchmarks only show 0-1 more fps for lower latency ram, but I've yet to see any benchmarks for actual memory bandwidth performance for ram intensive apps like photoshop.

 

[DoFoT9]

The latency difference between CL5 ddr3 1066 and cl7 ddr3 133 ram is like a 1 or so nanoseconds. What's more interesting is the theoretical 4gbps bandwidth that dual channel ddr3 1333 can provide vs the dual channel ddr3 1066. Gaming benchmarks only show 0-1 more fps for lower latency ram, but I've yet to see any benchmarks for actual memory bandwidth performance for ram intensive apps like photoshop.

there is still a lot more room for improvement seeing as though the chipset supports up to 12.8GB/s. i wonder if we will get to that limit lol.

 

[TMRaven]

To what chipset are you referring? Lynnfield supports up to 21gb/s bandwidth. Two DDR3 1066 sticks give you around 17gb/s bandwidth while in dual channel mode, and dual channel ddr3 1333 sticks give you a theoretical 21gb/s.

Am I understanding it wrong? If not, that seems like a nice chunk of an upgrade.

 

[DoFoT9]

To what chipset are you referring? Lynnfield supports up to 21gb/s bandwidth. Two DDR3 1066 sticks give you around 17gb/s bandwidth while in dual channel mode, and dual channel ddr3 1333 sticks give you a theoretical 21gb/s.

Am I understanding it wrong? If not, that seems like a nice chunk of an upgrade.

woops mybad - i was referring to the P45 chipset for some odd reason. i blame lack of sleep

i have tried to find the memory bandwidth for the P55 chipset, intel doesnt specify though?!??! nowhere else can tell me either.

 

[DoFoT9]

well, i bit the bullet and grabbed some Geil 1x4GB 1066MHz CL7 RAM and chucked it into the computer!! ($166 aus for the chip).

WHAT A NIGHTMARE!!


i keep getting freezes and everything

my configuration is the original 2x2GB chips + the 1x4GB chip was in the 4th slot. my question is does this matter at all?

is anybody aware of the best RAM testing program? REMber doesnt really work very well as it can only allocate free RAM - not entire RAM. just want to see if its the computer thats not supporting it properly - or the RAM thats damaged.

Edit: ok ran AHT and everything passed on the quick diagnostics. WTF?

 

[REALIN]

well, i bit the bullet and grabbed some Geil 1x4GB 1066MHz CL7 RAM and chucked it into the computer!! ($166 aus for the chip).

WHAT A NIGHTMARE!!


i keep getting freezes and everything

my configuration is the original 2x2GB chips + the 1x4GB chip was in the 4th slot. my question is does this matter at all?

is anybody aware of the best RAM testing program? REMber doesnt really work very well as it can only allocate free RAM - not entire RAM. just want to see if its the computer thats not supporting it properly - or the RAM thats damaged.

Edit: ok ran AHT and everything passed on the quick diagnostics. WTF?

If I'm not completly off, with dual-channel memory isent it best to keep it to 2 or 4 sticks?

 

[DoFoT9]

If I'm not completly off, with dual-channel memory isent it best to keep it to 2 or 4 sticks?

from the research i did i dont think it effects it at all..

 

[aliensporebomb]

Aha!

Happy I found this thread as I'd read that the bus for the corei7 pretty much autodetects the speed of memory you have and adjusts accordingly.

I suspected it would work but didn't want to spend $200 or more on a hunch.

As it is with the DDR3 1066 mhz ram I'm still geekbenching over 10,000 but this implies I could get just a little more bandwidth out of the machine.

Thinking....thinking.....

I also wondered about this since the top iMac 27" Corei7 2.8 ghz machine (Fall 2009 refresh) in geekbench said it was running 1333 mhz DDR3 ram and I thought "everything else checks out that it's not a hackintosh, so maybe he really is running that".

Did a google search and found this thread a little while later. Cool.

 

[aliensporebomb]

Ah

well, i bit the bullet and grabbed some Geil 1x4GB 1066MHz CL7 RAM and chucked it into the computer!! ($166 aus for the chip).

WHAT A NIGHTMARE!!


i keep getting freezes and everything

my configuration is the original 2x2GB chips + the 1x4GB chip was in the 4th slot. my question is does this matter at all?

is anybody aware of the best RAM testing program? REMber doesnt really work very well as it can only allocate free RAM - not entire RAM. just want to see if its the computer thats not supporting it properly - or the RAM thats damaged.

Edit: ok ran AHT and everything passed on the quick diagnostics. WTF?

Because you would need to run TWO of those 4 GB chips for it to work properly.

 

[DoFoT9]

Because you would need to run TWO of those 4 GB chips for it to work properly.

woops, i forgot to update this thread. i eventually found that out! was quite angry when i figured it out, wasted my money! but its all ok now, i purchased some OWC paired memory and am running 12GB nicely thanks for the input

 

[aliensporebomb]

Ah

woops, i forgot to update this thread. i eventually found that out! was quite angry when i figured it out, wasted my money! but its all ok now, i purchased some OWC paired memory and am running 12GB nicely thanks for the input

Running the 1333 or the 1066?

 

[DoFoT9]

Ha

Running the 1333 or the 1066?

1066, im too scabby to fork out for 1333 besides, stock is still at 1066 anyway (2x2 + 2x4)

 

[AlienSexGod]

1333Mhz Hynix or Samsung ram that Apple uses on the new iMac 27" is not much more than 1066 gear.

100% confirm it works but even in the new macs only maybe 1% performance increase....

 

[aliensporebomb]

Ah

1% adds up over time however. I still maintain that I'm going to do this.

Stay tuned.

 

[NutsNGum]

1% adds up over time however. I still maintain that I'm going to do this.

Stay tuned.

BTW - this is my current performance with 1033 memory:

Image

Look at the date of the last post...

 

[aliensporebomb]

Ah

Look at the date of the last post...

I know. But I've always been fashionably or unfashionably late to every party.

All of us with i7 Macs from the 2009 batch should have sold with 1333 memory.

Conspiracy theory: The Intel i7 motherboards were "convertible" types that could run either 1067 or 1333 - I suspect that Apple did not spec them with the faster memory since at the time it was more expensive and the slower memory was more easily sourced at a lower price thus they could get higher profit margins from selling the slower chips.

See:
http://ark.intel.com/Product.aspx?id=41316

I will keep you posted as to my findings. Nothing new to the 2.93 and newer iMac users but for us older machines it is a bigger deal IMO. I want every bit of performance I can get out of this thing.

 

[aliensporebomb]

Final Update: G Skill 1333CL9S-4GBSQ work fine

Maxed my 2009 27" i7 iMac out with 16 gigs of the G-Skill SODimms.

NewEgg had a deal on them last week where if you bought them individually you could get $7 off on each chip so I saved $24 on a set of four bringing the price for 16 gigs to a ridiculous $102 with shipping.

Part is F3-10600CL9S-4GBSQ and boosted my Geekbench scores past my all time high:

I did a bunch of geekbench runs and it was almost like it thought it was running the old memory at first, then after running it a few dozen times I got that.

I still think I can get more out of the beast too - according to Geekbench mine is the highest scoring Corei7 iMac from the 2009 lineup if you check similar machines.