Dual Channel vs Single Channel Ram - Difference?

[The Day Dreamer]

For years I have been into believing that DUAL CHANNEL ram is faster. Out of nowhere, I got these threads and my belief system is shattered. Please shed some light on the matter with proof.


Attaching two links below.

http://www.reddit.com/r/buildapc/comments/1fcs77/discussion_ram_single_vs_dual_channel_speed/

http://www.gamersnexus.net/guides/1349-ram-how-dual-channel-works-vs-single-channel

 

[Termie]

There's actually nothing new in those threads. They show that dual channel RAM is faster. Running dual channel has always offered a 2-3% performance boost.

If running integrated video, it will provide a 20-25% performance boost in gaming.

Want proof?

Here's my test of an OC'd G3258 with one 4GB and two 4GB sticks in 3DMark.

4GB: http://www.3dmark.com/fs/3259506

8GB: http://www.3dmark.com/fs/3259417

Note that the CPU-intensive Physics scores are 2% faster with two sticks.

Frankly, unless you're on a budget and only want 4GB of RAM, there's no reason to buy a single stick. The arguments about buying a single 8GB stick make very little sense. Almost no one needs 16GB, and even if you had 2x4GB, you could always add another 2x4GB unless you're using an ITX board.

 

[Insert_Nickname]

For years I have been into believing that DUAL CHANNEL ram is faster. Out of nowhere, I got these threads and my belief system is shattered. Please shed some light on the matter with proof.

It matters a lot if you're running any sort of IGP. Proof should be very easy to find.

 

[mvbighead]

What has already been said.

RAM is already so fast that the difference is generally negligible unless using IGP.

I still always run it as it is the optimal configuration and it would generally be silly not to.

 

[BonzaiDuck]

Forum members are most likely to buy dual-channel kits as a rule.

I find it amazing, however, that some mainstreamers and businesses -- Yes, businesses! -- may purchase their computers from independent outfits without a clue as to "what's in the box."

My car-mechanic owns his shop -- it's his business. The office has two workstations. Sometime in the last three years, he bought two AMD systems from his "preferred" IT "provider." He was sold "two machines for the price of one."

In offering him advice to a problem of "sticky graphics" slowdowns, I discovered only a single, 8GB stick of RAM in each machine.

Further, the seller had underestimated my mechanic's needs. They access a large database of customers, parts, makes and manufactures, and a ponderous use of schematic diagrams.

The machines were provided only with integrated graphics. On the up side, my mechanic/repair-shop-owner arranged for redundancy in his HDD storage, but probably because he voiced his fears of disastrous data-loss to the IT seller.

 

[Insert_Nickname]

In offering him advice to a problem of "sticky graphics" slowdowns, I discovered only a single, 8GB stick of RAM in each machine.

Otherwise known as cost cutting.

Slightly OT, but AMD APUs benefit tremendously from dual channel memory. The manual for my Gigabyte F2A85XN actually has a sticker included "for optimal performance with HD video, please use dual channel DDR3-1333 minimum" (or something like that, can't recall the exact wording). Food for thought.

Intels HD Graphics can usually get by with a single channel, if you don't push the graphics too much.

 

[BonzaiDuck]

Otherwise known as cost cutting.

Slightly OT, but AMD APUs benefit tremendously from dual channel memory. The manual for my Gigabyte F2A85XN actually has a sticker included "for optimal performance with HD video, please use dual channel DDR3-1333 minimum" (or something like that, can't recall the exact wording). Food for thought.

Intels HD Graphics can usually get by with a single channel, if you don't push the graphics too much.

It was my initial assessment that his business requirements were hamstrung by the graphics. Someone here had suggested a possibility that it was the RAM, but at that point, I hadn't determined that it was a single 8GB stick -- thinking it was maybe 4GB (or less). I finally showed him that he could get a $75 mainstream video card with as much as 2 to (even!) 4GB vRAM, and his IT guy came back with the same assessment.

I could say that I might be "over-configured" with 16GB, but it comes in handy for the RAM caching.

 

[Insert_Nickname]

It was my initial assessment that his business requirements were hamstrung by the graphics. Someone here had suggested a possibility that it was the RAM, but at that point, I hadn't determined that it was a single 8GB stick -- thinking it was maybe 4GB (or less). I finally showed him that he could get a $75 mainstream video card with as much as 2 to (even!) 4GB vRAM, and his IT guy came back with the same assessment.

Don't forget graphics will cut a bit into the system memory capacity. The "standard" reserved chunk on Richland (properly Trinity/Kaveri too) is 768MB. So you get a total usable capacity of 7376MB. What's more the driver can allocate up to 2GB if necessary.

I always over-provision systems running on the IGP a bit for that reason.

I could say that I might be "over-configured" with 16GB, but it comes in handy for the RAM caching.

Nah. Just a bit of future-proofing. You can never have too much RAM...