does AMD Phenom II X6 1090T support memory above 1333MHz?

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colore

Limp Gawd
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hello

does AMD Phenom II X6 1090T support memory above 1333MHz?

thanks
 
Not officially. But most motherboards have options for DDR3 1600 and I've yet to come across someone who's had any issues from running memory at that speed(assuming memory is rated for 1600MHz).
 
unofficially, yes, i've ran 1600 since the 1090T's release
 
Technically, you're overclocking the CPU to run it at 1600 mhz speeds, but yes, you should be able to run it without any problems.
 
Tsumi said:
Technically, you're overclocking the CPU to run it at 1600 mhz speeds, but yes, you should be able to run it without any problems.
Click to expand...


nein, its just a multiplier change so that the ram runs at ddr3 1600 though you are putting more stress on the CPU-NB, but most am3 motherboards support it. though 1866(OC) is about the most the x6's can do. its the same thing with intel's i3/5/7 pre SB which only officially support 1333 or 1066(can't remember). but you obviously can run up to DDR3 2000 if the motherboard supported it.
 
Running 1600Mhz on the Ram with 3.6Ghz/4Ghz on the CPU since I got the chip on launch. So 1600 is definitely unofficially supported. It definitely gives the platform a nice little kick. Gives about 2-7% more performance from my experience.
 
1600 is ok through i had to up voltages on ram to 1,5 instead of 1,35 it's rated for intel chips.
 
sirmonkey1985 said:
nein, its just a multiplier change so that the ram runs at ddr3 1600 though you are putting more stress on the CPU-NB, but most am3 motherboards support it. though 1866(OC) is about the most the x6's can do. its the same thing with intel's i3/5/7 pre SB which only officially support 1333 or 1066(can't remember). but you obviously can run up to DDR3 2000 if the motherboard supported it.
Click to expand...

Yes, I'm running mine at 1866Mhz right now to overclock my 1055T to 3933Mhz. I have it running at stock voltage, but higher latency settings. When I had the 1055T at over 4Ghz I have had to reduce the memory to below 1600Mhz, but at the lower latency settings.

I was and still am a little concerned about stability, but so far I haven't had any problems running at the stock 1.65V. The memory does not like to run higher than 1866Mhz and I haven't tried upping the voltage on the memory to see if it will take it.
 
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I run mine at 1333 with a Cas of 6. At 1600 it seems to get a hitch in it. I don't know any other way to describe it..
 
colore said:
given these facts, I think 1600 is the optimum, not 1333
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I disagree. 1600 is the maximum, but you get almost no performance improvement going there:

7-Zip improves by %4

x264 improves by less than %1

GTA IV improves by %2

Average improvement 800 to 1066: %7

Average improvement 1066 to 1333: %3.5

Average improvement 1333 to 1600: %2.3

%7 is noticeable. %3.5 MIGHT be noticeable. But you'll never see the difference in %2.3.
 
sirmonkey1985 said:
nein, its just a multiplier change so that the ram runs at ddr3 1600 though you are putting more stress on the CPU-NB, but most am3 motherboards support it. though 1866(OC) is about the most the x6's can do. its the same thing with intel's i3/5/7 pre SB which only officially support 1333 or 1066(can't remember). but you obviously can run up to DDR3 2000 if the motherboard supported it.
Click to expand...

Just like changing the multiplier higher for BE chips is overclocking it. Point still stands is that you're overclocking the CPU, since the NB is on the CPU.
 
IMO Skip the DDR3 1333 modules, and purchase DDR3 1600 if you plan to OC. Even if just a little.

With a Phenom II or an X3 chip that unlocks the 4th Core to Phenom II chip like my Rana 455 unlocked.
(Which is recognized in CPU-Z/Cinebench as a AMD Phenom II X4 B55 Processor.)

ANyhow I played it safe, thought I wouldn't OC my rig when I purchased it 7 months ago. Then 2 months ago I went all out with OC'ing my system.

So now I run my DDR3 1333 @ 1280mhz with my 3.960Ghz CPU OC on all cores, If I had just purchased 1600 it would have most likely done 1333 speeds I'm getting plus 1600 speeds. Which is what my 3.960 OC natively wants. but my 1333 cannot run that fast so I have to down clock it a little with the OC and motherboard OC requirements. If I had to do it again on a Phenom II rig, I would go for DDR3 1600 memory that has been reviewed to do 1333 as well stable as 1600mhz, so then you can have both options.

I think Mushkin and Kingston are good brands when it comes to memory.
 
finally, I bought G.skill 1600

I am still searching for ways to increase responsiveness of my system, when I have many tabs opened in my web browsers

is it the amount of RAM? is it the speed of RAM? is it the latency of RAM? is it the speed of HD? is it the processor? is it the OS? (I have WinXP)

or it is just that software may be the bottleneck?
 
Tsumi said:
Just like changing the multiplier higher for BE chips is overclocking it. Point still stands is that you're overclocking the CPU, since the NB is on the CPU.
Click to expand...

You can raise the memory speed without changing the IMC speed. Most motherboards have a memory divider setting for 1600Mhz, which means the memory speed can be raised without upping the IMC frequency.
 
AMD chips love low latency so you will get better performance running low latency 1T at 1333 than a looser CL at 1600. Tony@OCZ did some in depth testing if you feel like googling.
Basically the conclusion was 1333 at CL7 > 1600 at CL8.

That being said I would still purchase 1600MHz ram and run it tighter at 1333 per the above example.

1600MHz+ is a must if you want to oc a non BE cpu or via HTT on a BE.
You might also find that you can run it at lower voltages too although YMMV. 1.35v LV ram is only binned 1.65v stuff.

EDIT: Another thing to note is that the higher in frequency you go (bandwidth) the faster nb speed you need. 2.6GHz on the nb is the minimum needed at 1600MHz to clear the bottleneck.
 
bbordwell said:
I hope you realize that CL8 @ 1600 is less latency than CL7 at 1333.
Click to expand...

Hmm, lets see the math:

1600Mhz = 6.25 × 10^-10 seconds * 8 cycles = 5 nanoseconds

1333Mhz = 7.50 × 10^-10 seconds * 7 cycles = 5.25 nanoseconds

guess so! ;)
 
Cheetoz said:
Hmm, lets see the math:

1600Mhz = 6.25 × 10^-10 seconds * 8 cycles = 5 nanoseconds

1333Mhz = 7.50 × 10^-10 seconds * 7 cycles = 5.25 nanoseconds

guess so! ;)
Click to expand...

You should actually use 800mhz and 667mhz but it still works out in favor of the 1600mhz ram.
 
defaultluser said:
I disagree. 1600 is the maximum, but you get almost no performance improvement going there:

7-Zip improves by %4

x264 improves by less than %1

GTA IV improves by %2

Average improvement 800 to 1066: %7

Average improvement 1066 to 1333: %3.5

Average improvement 1333 to 1600: %2.3

%7 is noticeable. %3.5 MIGHT be noticeable. But you'll never see the difference in %2.3.
Click to expand...

That's not a benchmark on an AMD platform, where speed/bandwidth/performance scaling is significantly different. AMD IMCs can benefit quite a bit from 1600Mhz memory (there is more performance-speed scaling when the speed is above 1333Mhz). A bump in the Northbridge speed also opens up significant amounts of RAM bandwidth.

All AMD motherboards are capable of setting memory at 1600Mhz (x8 multiplier, often undocumented), just the AMD CPU IMCs themselves are only rated for 1333Mhz. The reason for this is IMC limitation; according to this official AMD document, you would require an NB speed of 2400Mhz (above default 2000Mhz spec and requiring more than 1.15V) to not bottleneck 1600Mhz. NB speed must be 3 times the speed of the RAM (before DDR). 667 [1333 DDR] x 3 = 2000. 800 [1600 DDR] x 3 = 2400. However, if you overclock the NB to 2400Mhz and run 1600Mhz memory, you will see the performance benefit; otherwise you won't, so AMD did not bother rating the IMC at above DDR3-1333. If the IMC/NB were capable of being within spec to run 1600Mhz, then 1600Mhz would run with no problem across all of the AMD IMC revisions (C2, C3 and E0) and provide adequate performance benefit. And in most cases, the NB can be overclocked/overvolted to meet that minimum 2400Mhz spec.

As for the IMCs themeslves, on the Phenom II x6 (especially the 1090T) they are very robust. The Phenom II x6 can handle 2000Mhz RAM no problem.

I represent the Overclock.net AMD forums where I am among the reputable and respected by members for my knowledge. Does that answer your question?
 
i bought a 16GB 1866 g.skill kit for my 1100T/CHV combo. not that it really matters now as the OP has already made his RAM purchase. the benefit of 1333/1600/1866 etc aside, reason i bought my 1866 kit was to give me more RAM divider flexibility during OC'ing.
 
xd_1771 said:
That's not a benchmark on an AMD platform, where speed/bandwidth/performance scaling is significantly different. AMD IMCs can benefit quite a bit from 1600Mhz memory (there is more performance-speed scaling when the speed is above 1333Mhz). A bump in the Northbridge speed also opens up significant amounts of RAM bandwidth.

All AMD motherboards are capable of setting memory at 1600Mhz (x8 multiplier, often undocumented), just the AMD CPU IMCs themselves are only rated for 1333Mhz. The reason for this is IMC limitation; according to this official AMD document, you would require an NB speed of 2400Mhz (above default 2000Mhz spec and requiring more than 1.15V) to not bottleneck 1600Mhz. NB speed must be 3 times the speed of the RAM (before DDR). 667 [1333 DDR] x 3 = 2000. 800 [1600 DDR] x 3 = 2400. However, if you overclock the NB to 2400Mhz and run 1600Mhz memory, you will see the performance benefit; otherwise you won't, so AMD did not bother rating the IMC at above DDR3-1333. If the IMC/NB were capable of being within spec to run 1600Mhz, then 1600Mhz would run with no problem across all of the AMD IMC revisions (C2, C3 and E0) and provide adequate performance benefit. And in most cases, the NB can be overclocked/overvolted to meet that minimum 2400Mhz spec.

As for the IMCs themeslves, on the Phenom II x6 (especially the 1090T) they are very robust. The Phenom II x6 can handle 2000Mhz RAM no problem.

I represent the Overclock.net AMD forums where I am among the reputable and respected by members for my knowledge. Does that answer your question?
Click to expand...

ooh, thanks for info. knew you needed to up the CPU/NB during oc'ing but this 'specific' info is good to know (cut & pasted into my own personal PC overclocking notes). cheers.
 
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