Single Channel Dual Channel.. What the hell???

[bombasschicken]

Ok i got 2 sticks of PQI 1gb DDR Dual channel memory..
and one stick OCZ 512mb singl channel memory

when i have the 2 pqi i get dual channel at 200mhz ~ 2gb ram
when i have a pqi and a ocz i get single channel and 400 mhz ~1.5gb ram
and if i flip flop the pqi i get single channel at 200mhz ~ 1.5gb ram

WHAT THE HELL IS GOING ON HERE??

the rig:
ECS K8T890-A (<~~ yeah i know but it came in a combo kit..)
AMD 64 X2 3800+
Memory: well you know that already
PCI-E EVGA 6600GT

so what is the deal??
is it better to have 1.5gb @ 400mhz in single channel?
or is it better to have 2gb @ 200mhz in dual channel??

why is it 200 mhz in dual channel??

this lame ass dual channel crap is really starting to confuse me..

any help please!!?? Thanks..

 

[Czarles]

Dual channel is supposed to out perform single channel so use the two PQI sticks.

Are the PQI PC2100?



Please note I know nothing about dual channel or single channel. Take a nap and get at it after your bloodsugar and caffiene level is normal.

 

[thedrake]

...said this once in another thread....will say it again here, repeat after me...

There is no such thing as dual channel memory. It is the chipset/mobo that supports dual channel - any memory that fits into that chipset/mobo, will run in dual channel if you put the 2 sticks into the proper slots.

 

[thedrake]

as for what is going on, it is likely going with teh initial slot to determine which memory setting to go with......so when you flip them y ou get different answers.

Dump the 512 stick and go with the matching sticks, making sure you put them into the proper slots.


(for me it is slot 1 and 3 that are the first dual channel combo, and 2/4 is the 2nd...that I have empty).

As soon as you put in a 3rd, you will not be running dual channel, because the 4th is empty.......so dump the 512 and you will be better off.


[edit: I over simplified this and skipped details, but that in effect is the deal]

 

[bombasschicken]

Dual channel is supposed to out perform single channel so use the two PQI sticks.

Are the PQI PC2100?

No it is PC3200..

 

[bombasschicken]

as for what is going on, it is likely going with teh initial slot to determine which memory setting to go with......so when you flip them y ou get different answers.

Dump the 512 stick and go with the matching sticks, making sure you put them into the proper slots.


(for me it is slot 1 and 3 that are the first dual channel combo, and 2/4 is the 2nd...that I have empty).

As soon as you put in a 3rd, you will not be running dual channel, because the 4th is empty.......so dump the 512 and you will be better off

[edit: I over simplified this and skipped details, but that in effect is the deal]

Actually the mobo only has 2 memory slots.. so im kinda limited in that.. and im not sure if i explained it correctly but i getting thoes results using two...

im still confused because if i use the 2x1gb then i get only 200mhz.. but i get 400mhz when i use the 1x512 and 1x1gb...

i think im just going to live with 1.5gb and the 400mhz bus.. i get 10 more FPS in the doom3 test this way.. i dont know why...

 

[linux_0]

Ok i got 2 sticks of PQI 1gb DDR Dual channel memory..
and one stick OCZ 512mb singl channel memory

when i have the 2 pqi i get dual channel at 200mhz ~ 2gb ram
when i have a pqi and a ocz i get single channel and 400 mhz ~1.5gb ram
and if i flip flop the pqi i get single channel at 200mhz ~ 1.5gb ram

WHAT THE HELL IS GOING ON HERE??

the rig:
ECS K8T890-A (<~~ yeah i know but it came in a combo kit..)
AMD 64 X2 3800+
Memory: well you know that already
PCI-E EVGA 6600GT

so what is the deal??
is it better to have 1.5gb @ 400mhz in single channel?
or is it better to have 2gb @ 200mhz in dual channel??

why is it 200 mhz in dual channel??

this lame ass dual channel crap is really starting to confuse me..

any help please!!?? Thanks..

For best results you need a matched pair of memory sticks ( identical ).

Like this:

http://www.newegg.com/Product/Product.asp?Item=N82E16820145575

2x184pin DDR400 PC3200 SDRAM


If your memory sticks are not identical then the motherboard will have to slow down to the speed of the slowest memory module.

 

[cisco]

dual channel has to be in pairs. Can't run 3 sticks of memory in dual channel.

 

[bombasschicken]

i really hate it when people dont read...

I shall reiterate..
this board DOES NOT HAVE 3 RAM SLOTS.. it only has two.. i can only use 2 sticks of ram.. not 3.. only 2... thank you...

 

[thedrake]

Use the 2 same-size sticks!

That 400mhz you are seeing is a bad bios report. That is NOT correct.

There is no way in hell it is running at that.

The 2 matched sticks in dual channel will be far faster than the 1.5...

 

[RickRose]

Do you have the Ram timings of the 2 identical Ram modules? Sometimes the eager or just plain lazy bios updaters don't update the RAM dection timings properly therefore causing the motherboard to miss read your ram timings. Try to manually input the RAS/CAS timings to make sure the memory is represented properly. Just to be sure

Hope this helped!

 

[bombasschicken]

are you sure that mobo has dual channel capabilty? put both 1GB sticks in and go into your bios and see what it says their?

why does a motherboard without dual channel capability say "dual channel" at post? it has to have that capability.. right?

 

[linux_0]

are you sure that mobo has dual channel capabilty? put both 1GB sticks in and go into your bios and see what it says their?

why does a motherboard without dual channel capability say "dual channel" at post? it has to have that capability.. right?


Yes it IS a dual channel board.

For best results you need 2 IDENTICAL memory sticks.

You can combine different sticks but you cannot expect it to work correctly.

Your memory sticks are also different sizes that configuration is unsupported.

 

[linux_0]

are you sure that mobo has dual channel capabilty? put both 1GB sticks in and go into your bios and see what it says their?

why does a motherboard without dual channel capability say "dual channel" at post? it has to have that capability.. right?


Yes it IS a dual channel board.

For best results you need 2 IDENTICAL memory sticks.

You can combine different sticks but you cannot expect it to work correctly.

Your memory sticks are also different sizes that configuration is unsupported.

Dual-channel architecture DDR SDRAM describes a motherboard technology that effectively doubles data throughput in the frontside bus from RAM to the memory controller. Dual Channel-enabled memory controllers utilize two 64-bit data channels, resulting in a total bandwidth of 128 bits, to move data from RAM to the CPU.

In order to achieve this, the DDR SDRAM memory modules must be installed into matching memory slots, which are usually color coded on the motherboard. Each memory module in each slot should be identical to the one in its matching slot. It's also possible to use similar memory sticks from different manufacturers or different production series as long they are of the same size, specification, the same number of memory chips and internal organization.

 

[bombasschicken]

are you sure that mobo has dual channel capabilty? put both 1GB sticks in and go into your bios and see what it says their?

why does a motherboard without dual channel capability say "dual channel" at post? it has to have that capability.. right?


Yes it IS a dual channel board.

For best results you need 2 IDENTICAL memory sticks.

You can combine different sticks but you cannot expect it to work correctly.

Your memory sticks are also different sizes that configuration is unsupported.

Dual-channel architecture DDR SDRAM describes a motherboard technology that effectively doubles data throughput in the frontside bus from RAM to the memory controller. Dual Channel-enabled memory controllers utilize two 64-bit data channels, resulting in a total bandwidth of 128 bits, to move data from RAM to the CPU.

In order to achieve this, the DDR SDRAM memory modules must be installed into matching memory slots, which are usually color coded on the motherboard. Each memory module in each slot should be identical to the one in its matching slot. It's also possible to use similar memory sticks from different manufacturers or different production series as long they are of the same size, specification, the same number of memory chips and internal organization.

perfect.. now i have a better understanding of dual channel.. although my origional question was not answered.. im just going to leave it at a crappy motherboard.. ECS was never any good to me anyways..

thanks everyone...

 

[Anoobis]

Dump the 512 stick and go with the matching sticks, making sure you put them into the proper slots.

(for me it is slot 1 and 3 that are the first dual channel combo, and 2/4 is the 2nd...that I have empty).

As soon as you put in a 3rd, you will not be running dual channel, because the 4th is empty.......so dump the 512 and you will be better off.

Your thinking of a Socket A board, in which case you'd be correct, however the OP is using a socket 939 board.

That 400mhz you are seeing is a bad bios report. That is NOT correct.

There is no way in hell it is running at that.

The 2 matched sticks in dual channel will be far faster than the 1.5...

Again, we are dealing with S939, so 400MHZ is possible. However you're correct in that the OP should stay with the 2 matched sticks.

To the OP. Download the manual. Pages 14-17 should help clear up the confusion. Especially pages 16-17.

 

[Hawkeye22]

I didn't see anyone mention this, but isn't a 200mhz fsb/htt DDR400, thus the double data rate? My bios reads as 200mhz, but at post it shows dual channel DDR400 128 bit. When I oc to 220mhz 1:1 I get DDR440.

 

[Anoobis]

That's what I meant by 400MHZ is possible.

BTW, 400MHZ is also possible with Socket A. I know because that's what my Athlon XP-M 2600's memory is running at. Also the last XP Barton's released supported 400 FSBs.

bombasschicken, don't be ashamed by your 7600GS. From what I hear it's a solid card for the money.

 

[maury73]

Let's make some clearness

200MHz reported by BIOS settings is correct, beacuse it's the real SDRAM clock frequency and isn't related with the HTT speed at all (remember that HTT on AMD is not like FSB on Intel!).

DDR400 is the Double Data Rate speed: the memory exchanges data at 400MHZ because it uses both edges of the 200MHz clock, but all the commands are synchronized with and sent at 200MHz clock speed.

Related to the dual channel stuff, the previous posts are correct: you must have 2 modules of the same size, speed and timings in order to use dual channel capability.
Dual channel is not a capability of the RAMs itselves, it is a capability of the RAM controller: in practice the two slots are configured in parallel, doubling the thoretical maximum bandwidth, but obviously the two DIMMs have to be identical in size and speed to do so.

 

[Dahak]

dual channel out performs single channel by doubling the memory bandwidth by the chipset.now on most older dual channel boards you can run two sticks of similar ram in the apropriate slots and you get dual channel.however,todays boards (like my evga) are more finicky and require identical ram or it will only read as single channel.as for putting a third stick in,make sure it is the same make and size and speed as others.else you will get the problems you are having now.hope i have helped.

evga nf4 sli mainboard
athlon 3500+(soon to have a 4400+dual core)
7800gt
2x1gig samsung ddr400(dual channel)
wd 300 gig hd.
ace 520watt ps

 

[thedrake]

Dump the 512 stick and go with the matching sticks, making sure you put them into the proper slots.

(for me it is slot 1 and 3 that are the first dual channel combo, and 2/4 is the 2nd...that I have empty).

As soon as you put in a 3rd, you will not be running dual channel, because the 4th is empty.......so dump the 512 and you will be better off.

Your thinking of a Socket A board, in which case you'd be correct, however the OP is using a socket 939 board.

That 400mhz you are seeing is a bad bios report. That is NOT correct.

There is no way in hell it is running at that.

The 2 matched sticks in dual channel will be far faster than the 1.5...

Again, we are dealing with S939, so 400MHZ is possible. However you're correct in that the OP should stay with the 2 matched sticks.

To the OP. Download the manual. Pages 14-17 should help clear up the confusion. Especially pages 16-17.

First, my board is a s939 board and if I don't use 1 & 3 for my sticks, it does not report it as dual chanel. If I use 1 & 2 for example it goes single channel.

Second, I'm well aware that 400 is possible, not with what he put in it! He stuck it in rebooted and it reported it one way, all he did was flpy the 2 different size sticks around and tried again and it mis-reported it. So based on what he did, it is impossible for it to be running at that.

 

[Anoobis]

Ooops, my bad. I misread your initial post. Didn't see the 2/4 part.

 

[joex444]

perhaps this is a little OT at this point, but yes you can. maybe a 939 won't allow it, but I have 3 sticks in dual channel on a socket A that are quite happy. channel A -- two 256MB OCZ & channel B -- one 512MB GeiL, dual channel 400MHz 2.5-3-3-6-1T. ok, i'll grant you it was a pain to get it working, but they work. some combinations wouldn't POST, some would give errors, but there was a way to do it.

 

[maury73]

joex444 is right: in theory it doesn't matter the size of each module, what counts is the total amount of RAM installed in each channel.
I have 2x512MB modules in channel 0 and 1GB module in channel 1 in an A8N and it worked great since the first boot.

However It doesn't works on all mobos because of bugs or limitation in BIOS FW, but the RAM controller itself doesn't matter for the single module size: the two channel configurations are totally independent (except for frequency and timings that *MUST* match) if it doesn't work it's a FW related problem.

At work we design system boards for very high speed realtime image processing and we tested theese strange configurations with Intel, AMD and Freescale, and always worked fine with well written FW.

 

[Anoobis]

Yes, I'd be interested in seeing some CPUZ screenshots of that.