Dual Channel RAM Guide

Yup, that's exactly what it seems like, I just wanted to see benchmarks to confirm it for the 965M chipsets.

 

No problem! People need to challenge things! I am happy I held up to the test!

 

For those people who want to know what single channel memory performance looks like, I have run some tests on the Sony G11 notebook which uses the Intel 945GMS chipset which supports only a single channel memory channel (to save power, I presume). So, even if there are two RAM modules (one is integrated) it still only runs single channel.

The G11 also has a switchable memory speed: 533MHz is the normal speed but 400MHz is available for lower power consumption. The attached results show a Single channel memory bandwidth of about 2211MHz at 533MHZ RAM frequency and 2014MHz at 400MHz RAM frequency.

These results show that the single channel bandwidth is approximately half of the dual channel / asymmetric dual channel results posted earlier in this thread and also that the 33% boost in memory speed between 400 and 533MHz results in about only a 10% increase in bandwidth due to the higher latency.

John

 

Being a newbie all this is a bit too technical for me. I have a "simple" question. To upgrade my RAM for the fastest speed do I buy DDR-SDRAM 667Mhz to be compatible with what I have in my computer? Should I spend the money to get 2x2gb even though I understand that windows will not recognize the 4gb total or just buy 1gb + 2gb or just leave things as they are? I am running Vista home premium.
Thanks
Dave


_______________________________________________________________
MY COMPUTER
VGN-FZ190CTO with Blu-ray, NVIDIA GeForce 8400M GT, 15.4" WXGA (HC) W/CMR, 160GB HD, 2GB DDR-SDRAM, Core 2 duo T7700 / 2.4 GHz,

 

Well, you need to check whether or not your motherboard supports 2GB SODIMMs. Windows will see up to 2.8GB IIRC, unless you get the 64bit version, which in that case, you can use the full 4GB (if your mother board supports it).

 

Sony gave the option to customize the computer up to 4 gb of RAM - is that what you mean?

 

That indicates the hardware supports, and I believe Vista 32 can see as much as about 3.2 max and less in many cases because of hardware. So with 64 you should be able to use the full 4GB's of RAM.

 

I now have 2gb ram. What if I like the Vista 32 and I just want to maximize the RAM do I upgrade to 3gb or 4gb in total for fastest speed or do I just leave things as they are 2gb?
Thanks
Dave

_______________________________________________________________
MY COMPUTER
VGN-FZ190CTO with Blu-ray, NVIDIA GeForce 8400M GT, 15.4" WXGA (HC) W/CMR, 160GB HD, 2GB DDR-SDRAM 667Mhz, Core 2 duo T7700 / 2.4 GHz,

 

So anyone test if things are faster with 2x1GB vs 1GB+2GB vs 2x2GB? I suppose if you have the money, might as well go for 2x2GB and 32-bit. It doesn't really matter if you lose a bit.

 

better to upgrade CPU than upgrading RAM from 2G to 3G.

 

If money was not an issue maybe? I still think I disagree. 2GB stick is what $90 a CPU upgrade? OK going up one level in CPU is not going to make a difference so what will it cost him to upgrade to the best available? I don't know but isn't $500 close? And few programs make use of a 2.4GHz C2D anyway. Also even though it is PGA if it goes bad big problem. Just my thoughts, to each his own.

 

Guys my cpu is a 2.4Ghz already.
Once again I now have 2gb ram. What if I like the Vista 32 and I just want to maximize the RAM do I upgrade to 3gb or 4gb in total for fastest speed or do I just leave things as they are 2gb?
MY COMPUTER IS A SONY LAPTOP VGN-FZ190CTO with Blu-ray, NVIDIA GeForce 8400M GT, 15.4" WXGA (HC) W/CMR, 160GB HD, 2GB DDR-SDRAM 667Mhz, Core 2 duo T7700 / 2.4 GHz,
Thanks
Dave

 

If the applications you run can benefit from more than 2GB ram, then you should buy more than 2GB RAM to get the fastest speed.

Vista is capable of utilizing up to around 3.5GB, but if you only play minesweeper, you won't benefit much from adding more RAM.

 

At one time I have open: typically 5 or 6 internet explorer windows with multiple tabs as well as itunes, quicken, outlook and word documents. Do you think I will benefit with the more RAM?

 

Your computer most likely has a little light that blinks when you go to the HDD. Once all your stuff is open and therefor in memory if room, start using and watch the light if it blinks a lot then it maybe going to HDD because memory is "full" if that is the case more might be beneficial, if very little HDD activity then more memory unlikely to make much difference.

 

Good advise. After checking I must say that the little light blinks on and off quite a bit. having said that what do you recommend for my computer which currently has 2gb ram and Vista 32 - do I upgrade to 3gb or 4gb in total for fastest speed?
MY COMPUTER IS A SONY LAPTOP VGN-FZ190CTO with Blu-ray, NVIDIA GeForce 8400M GT, 15.4" WXGA (HC) W/CMR, 160GB HD, 2GB DDR-SDRAM 667Mhz, Core 2 duo T7700 / 2.4 GHz,
Thanks
Dave

 

Don't bother with 4GB if you are staying with 32-bit Windows - you will see only 3GB. The memory bandwidth may be very slightly paster with two same sized modules, but that benefit is not worth the extra cost.

John

 

Thanks John. I like my 32 bit vista home premium but is it worth upgrading that to the 64 bit vista? Will that be faster with a 4gb RAM over the 32 bit with 3gb RAM. My computer is a Sony laptop VGN-FZ190CTO with Blu-ray, NVIDIA GeForce 8400M GT, 15.4" WXGA (HC) W/CMR, 160GB HD, 2GB DDR-SDRAM 667Mhz, Core 2 duo T7700 / 2.4 GHz,
Thanks
Dave

 

64 bit OS are just starting to get a foot in the market. As such most programs are not written to maximize the advantage of the 64 bit capabilities. Therefor real world you will likely not see a difference. So if you like your 32 bit OS no reason to change yet. In the future when the majority of OS used are 64 bit yes I think you will see advantages. Just like now many programs no longer support Windows 98 that day will come for 32 bit OS but not here yet and for that matter I would guess 2 to 4 years, maybe more.

 

Hi, I plan to upgrade from 2GB (1x1GB) RAM to 4GB (2x2GB). I'm using Windows Vista Home Premium 32bit for now, but I'm formatting and installing Vista Ultimate 64 in a few weeks. I wanted to know if I would receive a performance increase if I ordered a single 2GB stick of RAM and took out one of the 1GB sticks of RAM currently installed on my notebook and installed the 2GB stick alongside the other 1GB stick for a total of 3GB. I plan to first upgrade to 3GB then to 4GB, so I was just wondering if 3GB would temporarily provide much of a performance boost with Vista Ultimate 64 in comparison to having 2GB at present time. The RAM I’m purchasing is exactly the speed as what I have installed on my notebook.
I appreciate any help.

 

You will only see a performance increase if you use apps or perform tasks which can use more than your current 2GB. What kind of work do you do on your laptop?

 

I do 3D Modeling with 3D Studio Max and CINEMA 4D, photoshop, Maple, and when I have some free time I game a little. When performing normal tasks 2GB is alright, but for example when I have a bunch of 3D Max applications open along with photoshop, computer slows down a little. I just wanted to know if 3GB not being evenly distributed (1GB + 2GB of RAM) would make an effect until I added another 2GB of RAM to replace the remaining 1GB for a total of 4GB.

Also perhaps installing Vista Ultimate 64 along with 3GB would provide noticeable performance increase for applications and games like Crysis which at present time can take advantage of 64bit CPU's and more RAM? Crysis for example runs well enough at low-medium on my laptop without any of the stuff mentioned above, but I don't know if I'd see much difference upgrading or not.

 

You'd likely see a performance improvement going up to 3GB of RAM then, possibly even 4GB. Monitor your RAM and pagefile usage and see how much you use when you have several 3dmax apps going.

 

Alright, thanks for your help. Reputation added.

One more question though; I found that my laptop can take "200p PC2-4200 DDR2-533 SODIMM" memory from http://www.memoryx.net/.
I made a search in www.newegg.com and I found another 2GB stick of RAM which is also states "200-Pin DDR2 SO-DIMM DDR2 533 (PC2 4200)". Now newegg has it cheaper and I was wondering if memoryx as a source to finding out what types of RAM will work on my laptop is a legitemit source to follow and find RAM with the same exact specs at another location?

The reason I'm buying this RAM with these specs is so I can make use of the 2GB(2x1GB) sticks of RAM I take out of my present notebook after I upgrade on my old Dell Inspiron 9300 which also states at memoryx to take "200p PC2-4200 DDR2-533 SODIMM".

 

CPU-Z might be a better tool than the online ones. You have AMD so your FSB is effectively 800/1600Mhz. You should look at the documentation and see if you can run PC 5300/5400 667MHz and if you can I would buy that. I say to check your documentation because I believe a lot of these memory scanners just check what RAM you have to get compatibility. Now is the time to get the faster if your system can make use of.

 

Yep, my notebook supports PC2-5300 DDR2-667 200pin SODIMM as well, but what if the RAM installed on my laptop at present time is PC2-4300 or PC2-4200? I want to first upgrade to 3GB and then to 4GB, can I have one stick of 2GB PC2-5300 (667) in one slot and in the other a 1GB PC2-4200?

 

Yes, though both sticks will run at the slower (533mhz) speed. However it's probably worth it, because then when you upgrade to 4GB you'll be running at the faster 667mhz.

 

Great, appreciate all of your help guys.
All I can do is give reputation points.

 

Can you guys clarify something for me please?

When talking about dual channel, there is no difference as to whether you get a dual channel kit (say for example OCZ's 2x2gb kit) or buying 2 individual sticks of ram that are the exact same kind (say Corsair's single 2gb dimm, and getting 2 of em) They'll still both be dual channel correct? (as long as theyre the same speed)

 

Well, both sticks, even if they weren't the same, would work for dual-channel.

And I have a question, I have a Dell Inspiron 1520, with dual channel 2 x 1GB DDR2 667 mhz ram sticks. I want to change the setting to single channel to get a true 2Gb. Can I just change a setting in the BIOS of the motherboard (Intel 965 if I remember correctly), or do I need to open up my laptop?

 

To be honest, they don't even need to be the same brand or anything. As long as they're the same speed and capacity, you'll get true dual channel with no performance loss.

I'm not sure what you're asking. As long as you have 2x1GB, you have dual channel, which is a good thing. Why would you want to have 2GB in single channel?

 

Thanks for the response Odin! Looks like I have some thinking to do about what brand of ram I want hehe.

 

I don't think dual channel acts like RAID 1, so you should be able to utilise all your ram as 2GB as it doesn't store as two copies of 1GB

 

Hum, ok, so what do I do to change the setting to have a single-channel 2Gb with 2 x 1Gb ram sticks?

 

I don't think you can switch to single channel. It's not an option which people normally want since there's a performance hit.

If you really want single channel RAM then get a notebook with the Intel 945GMS chipset.

John

 

Again, WHY do you want single channel?

 

Dual channel is like dual water pipe connecting your shower. You cannot convert it to single channel, because each RAM channel is connected to the chipset. It's like serial vs parallel, you can't just go to the BIOS to change the settings, it's embedded on the motherboard.

If you want a 2GB single channel, you can get a single stick 2GB and stick it in one of the RAM slots. Though I wonder why people would want to do that, since you get performance loss as mentioned by a few posters above.

 

That's not actually true. Theoretically you could change a setting and have it be single channel, except that no one includes such a setting in their BIOS's, because there's no benefit to running in single channel.

 

Ok I got a major problem here, I received my 2GB stick of PC2-5300 RAM last week, but due to exams I didn't install it until now. Will I opened the bottom of my lapy, took out one of the 2x1GB stick of RAM replaced it with the 2GB stick, and booted up. Everything starts normally (faster of course ), but hers what I observed right away :

http://img478.imageshack.us/img478/5479/lapy3un9.jpg

You can clearly see under the Multi-meter program in Windows Vista Sidebar that the OS is recognizing 2813MB of system RAM instead of 3072MB it’s suppose to display. I’m not sure what the heck is up with this, but in BOIS it shows 3072MB as it should, but under both Multi-meter and My Computer it shows 2814MB. I’m running Windows Vista Home Premium 32, but I plan to format this Wednesday and install Vista Ultimate 64 instead. Before I do that can anyone explain what might be wrong here or if this issue will persist after a clean format?

 

There's nothing wrong, the extra ~256mb is being used by ATI's HyperMemory, and is not available to the OS.

Edit: Also, would you mind perhaps changing that pic to a link or thumbnail?

 

That's wired; it did do that under 2GB. Plus I though HuperMemory didn't grab system shared memory unless it needed it at a particular time. I presumed like before it would just allocate shared memory and only try to access it in a time of need, not reserve/restrict it at all times.

 

I would assume that once you have above a certain amount of available RAM, the system decides that you have enough to permanently dedicate some of it to the graphics card. Did you see the full 2048mb when you had 2GB?

 

Yep, it displayed 2048MB at all times, but you got a point before the upgrade Windows Vista when I right clicked on desktop/properties/display/advanced/adapter showed around 760MB Total Available Graphics Memory for when I had 2GB of RAM, but now it apparently has bumped it to 1279MB Total Available Graphics Memory after the 3GB install. Still though under the System Video Memory it still shows "0 MB" in use, but like you said maybe after certain amount of RAM Vista will store away some of that memory as inaccessible by anything other than the GPU.

 

Yup, that confirms it. Vista's reporting an additional 519mb of graphics memory available, which is exactly double the memory you lost. (As Vista can allocate an additional 259mb for the 259mb that Hypermemory has taken from the system RAM).

 

good job, too bad you were banned....??
would have rep pointed ya.....
you didnt sound like an angry soul, must have slammed someone pretty hard....
anyway, good article..

 

I read the article but I think my question still remeains unanswered

I have 2 Gbs of RAm one running at 667 and other running at 533, I used a program called CPU z, it said that I run at dual channel with the speeds of the RAM at 333mhz and 266mhz respectively.

Does that mean that my frquency is at a total of 600mhz?

Will there be a great improvement if I buy another one at 667mhz?(no money so please say that there is no great improvement)

 

Two points:

1. DDR2 RAM means that the data rate is double the clock speed, so what CPU-Z reports as 266 and 333 are actually 532 and 666.

2. It is unusual to have the modules running at different speeds. What is shown on CPU-Z's memory tab. This is the speed and timings actually in use. I would expect to see 266MHz + timings of 4-4-4-12.

These timings are the number of clock pulses required for the different memory access functions. If you increase the clock speed then the timings increase (to give the same physical time). The result is that the actual performance difference between 533MHz and 667MHz RAM. Both SiSoftware Sandra's memory bandwidth test and PCMark05 gave me increases of less than 70 in 3000 when switching to the faster memory. If you van find some 667MHz CL=4 RAM then the difference would be much bigger.

John

 

Thanks for the reply

So you are saying that there will be a great diffenrence if I upgrade my RAM to one that has 667mhz?

I have 237.5 DRAM frequency and as you said + timings of 4-4-4-12.

Is there a program that can help me increase it for the meantime?
Will switching back to 1 gb at 667mhz give me faster frequencies?

 

You misinterpret my comments.

In reality you won't see much, if any, difference in performance between normal RAM running at 533 or 667MHz. This RAM will switch from CL=4 @ 533MHz to CL=5 @ 667MHz.

There is said to be some RAM which is rated as CL=4 @ 667MHz, which would be a little faster.

The only other way to speed up your RAM is to find one of the software packages such as ClockGen or SetFSB which allows you to speed up the timing chip and run both the CPU and RAM faster than normal. However, unless you can find someone who has done it before with the same computer and has reported the settings, I would not recommend this approach.

John

 

Oh ok Thank You for your patience in answering my questions.

I'll try other options