Running ram in Dual Channel vs Single Channel

AwesomeJay

Senior member
May 18, 2004
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does anyone have any links to tests done to show the difference with using dual channel over single channel in general or with the athlon 64?


thanks
 

philler

Member
Jan 6, 2005
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that's common knowlegde.. if you run dual ram you will get: broader spread and about 5-6% more out of your ram(especially when gaming) if you run in dual... and beside, the A64-socket 754 with single channel ram will soon be taken out of the market.. socket 939 with dual channel ram is certainly the best of the two A64-Sockets...

Philip
 

darbius

Member
Mar 18, 2005
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Okay, so question that follows up with his question above:

I have two DIMMs of 512MB and my motherboard (AMD) supports running in dual channel. Am I better off running those two DIMMs in single channel or dual channel?

For instance, I understand that apparently running dual channel on an AMD board only gives a 3-5% performance increase, however, is it still better than running in single channel?

Thanks.
 

robcy

Senior member
Jun 8, 2003
503
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Originally posted by: darbius
Okay, so question that follows up with his question above:

I have two DIMMs of 512MB and my motherboard (AMD) supports running in dual channel. Am I better off running those two DIMMs in single channel or dual channel?

For instance, I understand that apparently running dual channel on an AMD board only gives a 3-5% performance increase, however, is it still better than running in single channel?

Thanks.

If your board supports DC, and you have 2 stick of ram, then use DC. The difference between SC and DC on a Athlon 64 is more that just 5% (more like 10% to 15%). You can see this by noticing the signaficante cpu clock difference between same rated CPUs for the diffrent sockets. An example is that a socket 939 3200+ runs a slower clock than a socket 754 3200+ (200mhz), which demonstrates the performance diffrence between DC and SC since that is the only difference between the chips.
 
Nov 11, 2004
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Dual channel theoretically gives you twice the bandwidth.
DDR400/PC3200 gives you 3.2GB/sec of bandwidth while dual channel DDR400 gives you 6.4GB. That's only *theoretically*
 

darbius

Member
Mar 18, 2005
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Originally posted by: robcy
Originally posted by: darbius
Okay, so question that follows up with his question above:

I have two DIMMs of 512MB and my motherboard (AMD) supports running in dual channel. Am I better off running those two DIMMs in single channel or dual channel?

For instance, I understand that apparently running dual channel on an AMD board only gives a 3-5% performance increase, however, is it still better than running in single channel?

Thanks.

If your board supports DC, and you have 2 stick of ram, then use DC. The difference between SC and DC on a Athlon 64 is more that just 5% (more like 10% to 15%). You can see this by noticing the signaficante cpu clock difference between same rated CPUs for the diffrent sockets. An example is that a socket 939 3200+ runs a slower clock than a socket 754 3200+ (200mhz), which demonstrates the performance diffrence between DC and SC since that is the only difference between the chips.



My concern here is that running in dual channel mode would require me to run at 2T which would actually slow the system down and make it less effective than it would be in 1T mode, right? Or am I just confused? Thanks again.
 

bob4432

Lifer
Sep 6, 2003
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Originally posted by: robcy
Originally posted by: darbius
Okay, so question that follows up with his question above:

I have two DIMMs of 512MB and my motherboard (AMD) supports running in dual channel. Am I better off running those two DIMMs in single channel or dual channel?

For instance, I understand that apparently running dual channel on an AMD board only gives a 3-5% performance increase, however, is it still better than running in single channel?

Thanks.

If your board supports DC, and you have 2 stick of ram, then use DC. The difference between SC and DC on a Athlon 64 is more that just 5% (more like 10% to 15%). You can see this by noticing the signaficante cpu clock difference between same rated CPUs for the diffrent sockets. An example is that a socket 939 3200+ runs a slower clock than a socket 754 3200+ (200mhz), which demonstrates the performance diffrence between DC and SC since that is the only difference between the chips.


you are saying that the only difference in the chips is that one supports dc and one doesn't? this seems a bit oversimplified as to the difference between the skt939 and 754, could you please give more information into how these are the only differences...
 

redefine

Junior Member
Mar 9, 2005
4
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Your memory bus will be running at 128bits as apposed to 64bits, which theoretically doubles the bandwidth of the bus between the RAM and the CPU. So yes, definately take advantage of Dual-Channel whenever possible.
 

Amaroque

Platinum Member
Jan 2, 2005
2,178
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Originally posted by: bob4432
you are saying that the only difference in the chips is that one supports dc and one doesn't? this seems a bit oversimplified as to the difference between the skt939 and 754, could you please give more information into how these are the only differences...

Actually, My 754 3400+ (2.4 GHz stock) beats my 939 3500+ (2.2 GHz stock) in any CPU intensive app's. Of course, I run my 3500+ much faster then stock. So, for me this is a moot point.

Also, as everyone is saying, the main difference between 754, and 939 is the dual channel memory controller vs single channel memory controller. This is not oversimplified either, it's a fact.

The reason I said main difference is because the 939 sports a 1000 MHz HTT vs an 800 MHz HTT on the 754.
 

ribbon13

Diamond Member
Feb 1, 2005
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Originally posted by: darbius
My concern here is that running in dual channel mode would require me to run at 2T which would actually slow the system down and make it less effective than it would be in 1T mode, right? Or am I just confused? Thanks again.


2T happens when you run 3+ DIMMs. Dual Channel with just 2 is still 1T.
 

fstime

Diamond Member
Jan 18, 2004
4,382
5
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Dual channal will give you + ~1 fps in games, look in anandtechs artical, no performance gain.
 

issaid

Junior Member
Nov 10, 2003
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SO I jsut bought some PC2-5300 Geil Ram from newegg.
At first I wanted teh dual channel kit they have for 280.
It was out of stock so I bought 2x 1GB PC2-5300 for 141 each. On Geil site though it says it is single channel memory.

Is that because it is only one chip. And really all dual channel is, is 2 of the same chip? Because i do have that???

Thanks.
 

fstime

Diamond Member
Jan 18, 2004
4,382
5
81
Originally posted by: robcy
Originally posted by: darbius
Okay, so question that follows up with his question above:

I have two DIMMs of 512MB and my motherboard (AMD) supports running in dual channel. Am I better off running those two DIMMs in single channel or dual channel?

For instance, I understand that apparently running dual channel on an AMD board only gives a 3-5% performance increase, however, is it still better than running in single channel?

Thanks.

If your board supports DC, and you have 2 stick of ram, then use DC. The difference between SC and DC on a Athlon 64 is more that just 5% (more like 10% to 15%). You can see this by noticing the signaficante cpu clock difference between same rated CPUs for the diffrent sockets. An example is that a socket 939 3200+ runs a slower clock than a socket 754 3200+ (200mhz), which demonstrates the performance diffrence between DC and SC since that is the only difference between the chips.


15%, now thats just silly.

Anandtechs own words.

Quake 3 and other games based on the Quake Open GL engine are sensitive to memory bandwidth variations. So it was not a surprise to see Quake 3 increase in performance a bit over 6% from 754 to 939. Across all DX8 games 939 again came out as the top performer.