How much performance loss with 4x512MB vs. 2x1GB?

Glow

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Can someone clear this up for me? Or show me any articles?
 

BinarySynapse

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Depend on your system specs. I really haven't noticed any performance loss on my AMD rig with having 4x512. But upgradability is now limited. (price wise)
 

ToastMaster

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Theoretically, I think it's somewhere around 5-10%, depending on what type of application it is. Realistically, 2-3%.

I once asked this question several months ago on the SA forums, and a person who posts there who works at Corsair (I've always used Corsair ram until now) went over why the difference matters so little.

The primary time that performance loss is "greatest" is on A64 systems, since the system cannot handle 4 modules at 1T timing (defaults to 2T).
 

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ToastMaster said:
Theoretically, I think it's somewhere around 5-10%, depending on what type of application it is. Realistically, 2-3%.

I once asked this question several months ago on the SA forums, and a person who posts there who works at Corsair (I've always used Corsair ram until now) went over why the difference matters so little.

The primary time that performance loss is "greatest" is on A64 systems, since the system cannot handle 4 modules at 1T timing (defaults to 2T).

Mine does 4 sticks at 1T just fine.
 

Glow

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well Adding 2 more sticks of HyperX 3500 what do you guys think? Or what would you try for your settings at?
 

ToastMaster

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ryan_975 said:
Mine does 4 sticks at 1T just fine.

Are you running an Athlon 64 Socket 939 core or earlier?

Because... "Even before the E core revision had been released, some rumors circulated that this new core will allow giving up the 2T timing in systems with 4 double-sided memory modules. However, unfortunately, this has never happened. The CPUs based on this core can work with DDR400 SDRAM with 1T timing setting in all configurations except the one when we have 4 memory modules installed with at least two double-sided ones. And taking into account that most of the widely spread memory modules with 512MB capacity are double-sided, you can easily come across this particular situation with 4 double-sided DIMMs in the system."

http://www.xbitlabs.com/articles/cpu/display/athlon64-e3-mem_2.html

And from Anandtech :

"Why 1GB DIMMs?

In past memory reviews, we have said a lot about the impact of the 2T Command Rate on memory performance. We have speculated with others that the Rev. E AMD processor would remove the 2T requirement for 4 DIMMs, but in fact, the release Rev. E still required a 2T Command Rate with 4 DIMMs on the new on-CPU memory controller. So, what is the impact of going from 1T with 2 DIMMs to 2T with 4 DIMMs?"

Now, the DFI Lanparty UT RDX200 is able to have 4 modules of DDR400 at at 1T timing, but requires that the DDR400 be at stock speed - any type of overclock of the DRAM causes the timing to be set to 2T. As far as I know, this is the only board for Socket 939 and earlier Athlon 64s that allow a 1T timing of 4 modules. I maybe be wrong however.
 

SKy042

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I personally used to run 4x512MB OCZ Peformance series(copper heatspreader) on a ECS KN1 Extreme motherboard and a X2 4400+ last year.
It worked just fine for about a month before I wound up selling the rig to a friend.....he went with another motherboard and hasn't been able to duplicate it.
 

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ToastMaster said:
Are you running an Athlon 64 Socket 939 core or earlier?

Because... "Even before the E core revision had been released, some rumors circulated that this new core will allow giving up the 2T timing in systems with 4 double-sided memory modules. However, unfortunately, this has never happened. The CPUs based on this core can work with DDR400 SDRAM with 1T timing setting in all configurations except the one when we have 4 memory modules installed with at least two double-sided ones. And taking into account that most of the widely spread memory modules with 512MB capacity are double-sided, you can easily come across this particular situation with 4 double-sided DIMMs in the system."

http://www.xbitlabs.com/articles/cpu/display/athlon64-e3-mem_2.html

And from Anandtech :

"Why 1GB DIMMs?

In past memory reviews, we have said a lot about the impact of the 2T Command Rate on memory performance. We have speculated with others that the Rev. E AMD processor would remove the 2T requirement for 4 DIMMs, but in fact, the release Rev. E still required a 2T Command Rate with 4 DIMMs on the new on-CPU memory controller. So, what is the impact of going from 1T with 2 DIMMs to 2T with 4 DIMMs?"

Now, the DFI Lanparty UT RDX200 is able to have 4 modules of DDR400 at at 1T timing, but requires that the DDR400 be at stock speed - any type of overclock of the DRAM causes the timing to be set to 2T. As far as I know, this is the only board for Socket 939 and earlier Athlon 64s that allow a 1T timing of 4 modules. I maybe be wrong however.

Yes. Running an X2 3800+ Manchester (E4 I believe) and had a Athlon 64 3000+ (E3). Both ran 4x512MB DDR400 (been all the way up to 234 on my cheap ram*) 2.5-3-3-8 1T.

Jetway A210GMDS-Pro is my motherboard

*I didn't test running 1T while overclocked.

EDIT: Opened CPUz to get a screenie of my memory timings at was shocked to see that it was 2T even though the BIOS says 1T. Guess I was wrong about my X2. I do know for a fact though that my 3000+ ran 4x512 at 1T, just can't prove since I sold it. Now that I feel like a jackass, I'l hide from this thread for a while.
 

ToastMaster

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ryan_975 said:
Yes. Running an X2 3800+ Manchester (E4 I believe) and had a Athlon 64 3000+ (E3). Both ran 4x512MB DDR400 (been all the way up to 234 on my cheap ram*) 2.5-3-3-8 1T.

Jetway A210GMDS-Pro is my motherboard

*I didn't test running 1T while overclocked.

EDIT: Opened CPUz to get a screenie of my memory timings at was shocked to see that it was 2T even though the BIOS says 1T. Guess I was wrong about my X2. I do know for a fact though that my 3000+ ran 4x512 at 1T, just can't prove since I sold it. Now that I feel like a jackass, I'l hide from this thread for a while.

Well, there may have been more motherboards out there besides the DFI that was able to run it at 1T and 4 modules.

When I was originally researching what type of a performance hit I would take by using 4 modules with the X2 I had at the time, the Corsair person amongst others had told me about the issue with even the latest, E-stepping Athlon 64s and the 2T timing issue.

Thus, when I did decide to go the 4 module route, upon starting back up, I saw that it had downclocked my system to DDR333, at 2T, which is what the manual with my motherboard had said as well.
 

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ToastMaster said:
Well, there may have been more motherboards out there besides the DFI that was able to run it at 1T and 4 modules.

When I was originally researching what type of a performance hit I would take by using 4 modules with the X2 I had at the time, the Corsair person amongst others had told me about the issue with even the latest, E-stepping Athlon 64s and the 2T timing issue.

Thus, when I did decide to go the 4 module route, upon starting back up, I saw that it had downclocked my system to DDR333, at 2T, which is what the manual with my motherboard had said as well.


Same here, I installed an extra gig about two months ago and my system downclocked to DDR333 2T. I had to manuualy set it to DDR400 1T. It kinda irks me that my X2 won't do 4 sticks with 1T while my 3000+ would.
 

ToastMaster

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ryan_975 said:
Same here, I installed an extra gig about two months ago and my system downclocked to DDR333 2T. I had to manuualy set it to DDR400 1T. It kinda irks me that my X2 won't do 4 sticks with 1T while my 3000+ would.

I could go in and attempt to set the memory manually to DDR400 at 1T, but upon reboot it would be continually reset to DDR333 at 2T. It was aggravating, but not much I could really do at the time without spending more money for a new motherboard or 2* 1GB DDR400, making what I had just bought and what I currently had a waste.

Thankfully, my new system doesn't suffer from this issue.
 

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ToastMaster said:
I could go in and attempt to set the memory manually to DDR400 at 1T, but upon reboot it would be continually reset to DDR333 at 2T. It was aggravating, but not much I could really do at the time without spending more money for a new motherboard or 2* 1GB DDR400, making what I had just bought and what I currently had a waste.

Thankfully, my new system doesn't suffer from this issue.


I'll definately be glad when my cousin buys this system and I have the money to buy my C2D setup I want. Though I still haven't figured out exactly what C2D/motherboard I want.

The question remains though, is the performance loss from 1T to 2T greater than the performance loss from DDR400 to DDR333?
 

ToastMaster

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ryan_975 said:
I'll definately be glad when my cousin buys this system and I have the money to buy my C2D setup I want. Though I still haven't figured out exactly what C2D/motherboard I want.

The question remains though, is the performance loss from 1T to 2T greater than the performance loss from DDR400 to DDR333?

Honesty I'm sure it's comporable one way or the other.

For the C2D setup, I went with a P5B for now, until some time early next year when the motherboard selection is far greater, and hopefully an ASUS Republic of Gamer Intel board is out.

Memory wise, I went with the Crucial Ballistix DDR2 800, and it's working out great.
 

(cf)Eclipse

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ryan_975 said:
Same here, I installed an extra gig about two months ago and my system downclocked to DDR333 2T. I had to manuualy set it to DDR400 1T. It kinda irks me that my X2 won't do 4 sticks with 1T while my 3000+ would.
i bet you that your 3000+ "said" it was at 1T in the bios too, and was actually at 2T ;)
 

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(cf)Eclipse said:
i bet you that your 3000+ "said" it was at 1T in the bios too, and was actually at 2T ;)

No, it was 1T in CPUz too. I specifically remember that. I just assumed my X2 was as well since the 3000+ was.
 
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