DDR2 command rate

Pilgrim57 · 29 Jul 2007 at 11:29

What does it run at 1T or 2T?
Does it makes as much diffrence as DDR on a 939 mobo?

Jokester · 29 Jul 2007 at 11:31

Generally 2T, a few chipsets now support 1T though, 680i and P35 being ones I can think of off the top of my head.

And yes it does make a difference, but with all things memory timings wise it's barely noticeable in anything other than RAM benchmarks.

Jokester

w3bbo · 29 Jul 2007 at 11:32

You will struggle to get above 800mhz with 1T. 2T is the norm and is only slighly slower than 1T. There is a lot of difference with Intel - AMD with regards to command rate, intels performance is hardly dented using 2T.

helmutcheese · 29 Jul 2007 at 14:49

Before DDR2, AMD motherboards ran CPC-ON bioses thats 1T, CPC-OFF is 2T, CPC stands for Commands Per Clock and AMD did more commands per clock than Intel, hense AMD were faster at lower clocks.

DDR2 is now normally 2T, you can set some to 1T but not overclock as high, OCZ have kept there promise last week with DDR2 memory thats got some DDR3 function like this " 10-bit column address chips ".

They are also readying DDR2 with default of 1T, I think AMD's onboard memory controlers will work fine with this esp soon with newer AM2+ CPU and offical support for higher than 800mhz Memory.

Pilgrim57 · 30 Jul 2007 at 11:17

Jokester said:
Generally 2T, a few chipsets now support 1T though, 680i and P35 being ones I can think of off the top of my head.

And yes it does make a difference, but with all things memory timings wise it's barely noticeable in anything other than RAM benchmarks.

Jokester

I was specifically refering to Crucial Ballistix DDR 4000 on an Asus A8N-SLi Premium.
I can get it to run @ 3-4-4-10-1T 231MHz on 2.9v
I am folding for OcUK Team 10

& noticed that 1T would drop 5 mins off a 30 min frame @ 2T

Thanks guys for the DDR2 info

Pilgrim57 · 30 Jul 2007 at 12:48

helmutcheese · 31 Jul 2007 at 02:07

BTW, in DDR(1), flashing to a modded 2T bios on my Asus would give a performance drop, we had to try overclock the FSB an extra 10mhz to break even so an extra 15mhz to make it worthwhile.

I really looked upon it as a cheats way to get a higher FSB.

I had a 550mhz DDR FSB on a NF2 with 1T and in Dual channel mode anyhow.

roadie · 1 Aug 2007 at 11:40

I have 4x1Gb sticks of Geil Ultra on my abit KN9 Ultra (as per sig). At the moment the RAM is running at 800Mhz 2T, does anyone believe that it will work at 1T?

helmutcheese · 1 Aug 2007 at 17:43

Well as DDR2 its 2T, you could try 1T and it may be fine but may not overclock as high, I can run 800mhz with 1T but doubt it run 1000mhz with 1T.