System building, memory problem. Of sorts.

[Reubechs]

I'm helping a couple build a new rig, and we've run into a snag with memory. We're arguing (yes, actually) over amount of sticks versus bus speed vs latency. I'm pretty decent at throwing a machine together but we're getting downright specific as they're on a budget but still trying to squeeze every ounce of performance they can. Motherboard has yet to be decided, CPU is going to be a Core i5-2500 Sandy Bridge with the Z68 chipset.

I suggested a pair of 4gb sticks for a total of 8gb, plus DDR3-2133 which is quite fast and will keep it well under $100. Then I mentioned the latency might be a little high but the bus would make up for it, and it went downhill from there. The question now is: is a lower latency going to dent the bus speed that much? And with that, does having 4 sticks spread the load as much as sounds?

Example: four sticks (4x 2gb) of DDR3-1600 with a latency of, let's say, 7 would be faster/slower than two sticks (2x 4gb) of DDR3-2133 with a latency of 11 (my original selection). I can't imagine DDR3-1600 making up any difference no matter how low the latency is. They'll settle on something regardless, completion isn't contingent upon my giving them an answer.

[JustPlainJef]

With either latency (between one speed and the next) or bus speed, you are looking at maybe a 1 - 2% difference in speed. When I build my next rig, I'll be going with 8Gb of RAM, 2x4Gb sticks. I'm of the opinion that when you give a motherboard 4 sticks of RAM, it has to do more work to manage the load between them. I also know that for most users, 4Gb is even overkill.

Here's a link from Tom's, shows that the memory speed is more important that the timings. Look at the chart at the top, the PNY timings are the lowest, but they out-pace the Geil in one test and tie it in another.
DDR3-1866 Benchmark Results : Seven 8 GB DDR3 Memory Kits For Your AMD A75 Motherboard

This one shows the DDR3-1600 outperforming the DDR3-1833 in COD:MW2.
Making Memory Performance Matter Again : AMD A8-3850 Review: Llano Rocks Entry-Level Desktops

If you are on a budget, I'd get the highest bus speed you can find in your price range.

DDR3 1333 - Starting @ $35
Crucial DDR3 1333 (PC3 10600) CT2KIT51264BD1339

DDR3 1600 - Starting @ $38
Patriot DDR3 1600 (PC3 12800) PSD38G1600KH

DDR3 2133 - About $70 - $80 - Good speed bump, $40 extra well spent.
G.SKILL Sniper Series DDR3 2133 (PC3 17000) F3-17000CL11D-8GBSR
G.SKILL Ripjaws X Series DDR3 2133 (PC3 17000) F3-17000CL11D-8GBXL - CL11
G.SKILL Ripjaws X Series DDR3 2133 (PC3 17000) F3-17000CL9D-8GBXM - CL9 for $10 more. My choice, the RipJaw series is extremely popular.

DDR3-2400 - $160+ Not worth it.
GeIL EVO CORSA DDR3 2400 (PC3 19200) GOC38GB2400C11DC

[Reubechs]

Originally Posted by JustPlainJef

With either latency (between one speed and the next) or bus speed, you are looking at maybe a 1 - 2% difference in speed. When I build my next rig, I'll be going with 8Gb of RAM, 2x4Gb sticks. I'm of the opinion that when you give a motherboard 4 sticks of RAM, it has to do more work to manage the load between them. I also know that for most users, 4Gb is even overkill.



Here's a link from Tom's, shows that the memory speed is more important that the timings. Look at the chart at the top, the PNY timings are the lowest, but they out-pace the Geil in one test and tie it in another.

DDR3-1866 Benchmark Results : Seven 8 GB DDR3 Memory Kits For Your AMD A75 Motherboard



This one shows the DDR3-1600 outperforming the DDR3-1833 in COD:MW2.

Making Memory Performance Matter Again : AMD A8-3850 Review: Llano Rocks Entry-Level Desktops



If you are on a budget, I'd get the highest bus speed you can find in your price range.



DDR3 1333 - Starting @ $35

Crucial DDR3 1333 (PC3 10600) CT2KIT51264BD1339



DDR3 1600 - Starting @ $38

Patriot DDR3 1600 (PC3 12800) PSD38G1600KH



DDR3 2133 - About $70 - $80 - Good speed bump, $40 extra well spent.

G.SKILL Sniper Series DDR3 2133 (PC3 17000) F3-17000CL11D-8GBSR

G.SKILL Ripjaws X Series DDR3 2133 (PC3 17000) F3-17000CL11D-8GBXL - CL11

G.SKILL Ripjaws X Series DDR3 2133 (PC3 17000) F3-17000CL9D-8GBXM - CL9 for $10 more. My choice, the RipJaw series is extremely popular.



DDR3-2400 - $160+ Not worth it.

GeIL EVO CORSA DDR3 2400 (PC3 19200) GOC38GB2400C11DC

Thanks for the links.

We ironed out the arguement, they're going with CL7 DDR3-1600 as newegg doesn't seem to have the 1833 which is what they really wanted. Having seen our tax returns, I'm throwing together a new system as well and going with DDR3-2133. Those g.skills look like a fantastic buy, although I notice they're built with certain intel chipsets in mind. I've been a Mushkin fan for many years, never had a bad stick or a fit problem, but I'm also exclusively AMD.

[JustPlainJef]

I used to prefer AMD over Intel until my AMD PC couldn't keep up with any of the Intel builds my friends had, so I picked up an e8400. Since then, it doesn't seem that AMD can keep up with Intel in any sector. They used to be reasonable choices in the budget area, but now they can't even keep up with low-price Intel chips.

With video cards, however, it's a different story. I'm hoping to pick up my first ever ATI / AMD video card in the next few months. I'm looking to grab a HD7970 to push my three displays in an EyeFinity setup.