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View Full Version : Memory Command Rate vs. Pure Speed


TiKiMaN1
12-05-06, 02:48 PM
So which is faster for the Intel Core 2 Duo, memory running at 4-4-4-5 933MHz 1T or 5-5-5-15 1142MHz 2T?:D (note my signature)

:maxshoot:

I am uncertain how much the command rate even effects the Core 2 Duo anyway.:o

OrangeBlast
12-05-06, 03:07 PM
I always thought that 1T command was not even recognized by the C2D. I thought it always used a 2T command across the board. Tighter timmings are always nice but also thought that an AMD would better with tighter timings then the C2D.

Correct me if i'm wrong here (and I probably am) The C2D LOVES the mhz. Higher the better...

leave the ram at 2T 4-4-4-12 ( or something rather) and make sure your 1:1 and get the mhz as high as possible. You would see little to no difference with 1T and tighter timings with the C2D.

so I think.

TiKiMaN1
12-05-06, 03:11 PM
I always thought that 1T command was not even recognized by the C2D. I thought it always used a 2T command across the board. Tighter timmings are always nice but also thought that an AMD would better with tighter timings then the C2D.

Correct me if i'm wrong here (and I probably am) The C2D LOVES the mhz. Higher the better...

leave the ram at 2T 4-4-4-12 ( or something rather) and make sure your 1:1 and get the mhz as high as possible. You would see little to no difference with 1T and tighter timings with the C2D.

so I think.

That's what I was kinda thinking.;) Although the memory overclock in my signature is just screaming fast.:D

Roadhog
12-05-06, 03:14 PM
i ran these benchies with my memory.

1000Mhz 5-5-5-15 @ 2.7Ghz
Read: 7715 MB/s
Write: 5319 MB/s
Copy: 6028 MB/s
Latency: 58.5 ns

889Mhz: 5-5-5-15
Read: 6843 MB/s
Write: 4720 MB/s
Copy: 5341 MB/s
Latency: 65.9 ns

800Mhz:
Read: 6641 MB/s
Write: 4718 MB/s
Copy: 5344 MB/s
Latency: 69.2 ns

533Mhz
Read: 5479 MB/s
Write: 4731 MB/s
Copy: 4845 MB/s
Latency: 80.7 ns

TiKiMaN1
12-05-06, 03:20 PM
i ran these benchies with my memory.

1000Mhz 5-5-5-15 @ 2.7Ghz
Read: 7715 MB/s
Write: 5319 MB/s
Copy: 6028 MB/s
Latency: 58.5 ns

889Mhz: 5-5-5-15
Read: 6843 MB/s
Write: 4720 MB/s
Copy: 5341 MB/s
Latency: 65.9 ns

800Mhz:
Read: 6641 MB/s
Write: 4718 MB/s
Copy: 5344 MB/s
Latency: 69.2 ns

533Mhz
Read: 5479 MB/s
Write: 4731 MB/s
Copy: 4845 MB/s
Latency: 80.7 ns

What memory benchmark are you using?

Blacklash
12-05-06, 05:32 PM
Other settings like tRFC can be critical for ram. Some motherboards default to 35-42 for that setting which is a$$. I've found refresh mode to effect performance as well, example; 15.6, 3.9 or 7.8. My rig screams on 3.9. Tight tRAS helps immensely too, at least for "felt" speed when using your rig. Naturally, CAS and RAS to CAS are vital too.

If I want to volt up my memory I can do 3-3-3-4 tRFC 13 @ DDR 826.

If 1T is indeed working I'd think it would be equal to very high speeds @ 2T. Eventually you could catch it with 2T and you'd need hella fast memory to do it.

Hopefully the new BX2 I have with the 1333 strap will enable me to return to testing around DDR 1150 like I could on 965 with this memory.

Road's benches are interesting. Seems 1:1 has the highest latency.

TiKiMaN1
12-05-06, 06:05 PM
I will work on my tRFC and see how that changes things.:D

Lazaredz
12-05-06, 11:55 PM
I also would be interested in these findings.

TiKiMaN1
12-05-06, 11:56 PM
I also would be interested in these findings.

Man you got one sweet rig! That is all I have to say.:D I hope that you enter your rig in the competition.

(nana2)

Blacklash
12-06-06, 01:53 AM
Tiki,

What sort of SuperPi1m times do you get with that memory @ it's max speed @ a 1T setting? I'm actually wondering how your max 2T and 1T settings stack up under that bench.

Xion X2
12-06-06, 02:45 AM
i ran these benchies with my memory.

1000Mhz 5-5-5-15 @ 2.7Ghz
Read: 7715 MB/s
Write: 5319 MB/s
Copy: 6028 MB/s
Latency: 58.5 ns

889Mhz: 5-5-5-15
Read: 6843 MB/s
Write: 4720 MB/s
Copy: 5341 MB/s
Latency: 65.9 ns

800Mhz:
Read: 6641 MB/s
Write: 4718 MB/s
Copy: 5344 MB/s
Latency: 69.2 ns

533Mhz
Read: 5479 MB/s
Write: 4731 MB/s
Copy: 4845 MB/s
Latency: 80.7 ns

Am I missing something? I don't see where you lowered the timings any.. just the speed.

Dazz
12-06-06, 11:46 AM
T1 as far as i am aware is only supported by the nForce 680i boards.

J-Mag
12-06-06, 11:58 AM
T1 as far as i am aware is only supported by the nForce 680i boards.

You are referring to intel C2D boards only, right?

Dazz
12-06-06, 01:19 PM
Yeah of coruse the 680i are only for Intel at this moment in time. Bare in mind the memory controller is not intergrated into the CPU and is in the north bridge. So yech a change in board can support it.

J-Mag
12-06-06, 01:23 PM
Yeah of coruse the 680i are only for Intel at this moment in time.

What I meant is there are plenty of other boards that will run in 1t. Also, the memory controller isn't the only factor. I remember some AMD boards wouldn't run 1t, most likely due to the trace length or something with the memory circuit.

Xion X2
12-06-06, 06:50 PM
Some AMD boards wouldn't run 1T w/ 4GB of memory installed, but would run it w/ 2GB. I believe all nForce4 boards were like that.

J-Mag
12-06-06, 06:55 PM
Some AMD boards wouldn't run 1T w/ 4GB of memory installed, but would run it w/ 2GB. I believe all nForce4 boards were like that.

I don't think it is the size of the Dimms that cause the problem just the number. Like 4 dimms = 2t and 2 dimms = 1t.

Also, my a8n-sli wouldnt run well with 1t and 2dimms but it was the first rev. (i HAD to have SLI when it came out).

Dazz
12-06-06, 07:23 PM
It was they couldn't run @ T1 with 4 banks of double sided DIMM's i think they fixed that with the AM2 however. The DFi RD580 aparrently fixed it but you could overclock at all.
No one knows who they fixed it as it's a memory controller limitation, As far as i am aware the Core 2 nForce 680 boards allows T1, Intel boards does not give you the option but
run at T2.