CL3 vs CL2

[chinny]

Hi,

Am looking to get 2Gb of RAM to upgrade my machine (unfortunately only 3 slots and need to maintain dual-channel). I'm running MCE and playing BF2 on it - current 1Gb not doing too well and some people on here advised that 2Gb would make quite a difference to this. I'm looking at either the Corsair Value select 2gb pack or the TwinX 2gb pack. The price difference is almost double for the TwinX so what I really need to know is will it actually make that much difference?

Many thanks.

[Nox]

A website did a comparison of value vs expensive memory fairly recently, was reading about it. I'm pretty sure the conclusion was the latency could account for between 1 an 10% depending on the specific test, (ie pretty low) but the crunch was that the value did not overclock at all well. So if you wanted to overclock, spend out the cash, and if you're happy to run at stock, get the value.

If only I could remember which website it was now... Was when I was trying to find a (recent) comparison of DDR to DDR2 memory.

Nox

[chinny]

Thanks Nox,

I guess for such a small performance gain I'll not bother then - can't justify the extra cost. If you do remember the link to the site I'd be interested to see the comparison.

[Agent]

unfortunately only 3 slots and need to maintain dual-channel

Why ?
You do know you will get some benifit even if using all 3 slots ?

[chinny]

Yeah - I accept that but surely running dual channel will make quite a difference to the memory performance - anyone got any benchmarks to either prove or disprove this?

[Dark Horse]

Dual Channel is a bit of a myth....the performance increase is ~5%

Any ram can run dual channel, its the slots you put it in not the actual ram so as long as you have a minimum of 2 sticks of ram you can run dual channel.

http://www.devhardware.com/c/a/Memory/Dual-Channel/1/

The same with cl2 and cl3, the difference is ~5% aswell

[Agent]

Yeah - I accept that but surely running dual channel will make quite a difference to the memory performance - anyone got any benchmarks to either prove or disprove this?

Dual channel is largely a con. The difference in real world is a few frames here and there. If your expecting massive jumps from it, you wont get them.

http://www.sudhian.com/showdocs.cfm?aid=480
http://www.sudhian.com/showdocs.cfm?aid=483

The point of all this isn’t to point fingers or level blame on Intel or AMD for “deceiving” buyers (especially at this juncture), its to shed light on how a simple statistic can become a marketing force capable of justifying vast premiums for products that offer only minimally more performance than their lower-priced cousins. It’s a high-tech version of the Emperor’s New Clothes, a game of one-upmanship where neither side is willing to admit how far from reality the game has gotten. Why did Intel focus on memory bandwidth? Because it was a big number they could tout. Why did AMD focus on dual-channel configurations? Because Intel had dual-channel configurations. And everyone (even the people for whom it couldn’t possibly matter) bought into it, because we learned somewhere along the way that two is better than one.

About a year old, but its still largely correct.
You'll get some gain, but all this marketing that the memory companys put out making you think its a huge gain is BS.

Dont get me wrong, any gain is welcome, but the extra money it will cost you to get "cerified" RAM is a rip off. Plus the fact that you done need "dual channel packs" for it to work.

[kalniel]

The difference between CL2 and CL3 is virtually none. The biggest difference is with the command latency timing (1T or 2T), but either way it doesn't translate into any noticable real world difference.

In my experience dual channel has actually made a noticable (but small) difference, as has running at 200mhz rather than 166mhz. But as stated above, you don't need kits to run dual channel at all. (note - whether you notice a difference will depend on your usage - I doubt much would be noticed for gaming)

But yeah, unless you want to overclock there's no reason going for the more expensive memory.

[chinny]

Right,

Just ran a benchmark with 2 x 512Mb. Once in single channel mode and then again in dual channel mode. I benched using latest Sandra Lite and ended up with 36% increase using dual-channel....as to if it would make any difference in a game or not though.....

Thanks for the replies.

[madkez]

exactly the same situation i'm facing......go for cl3 or cl2? about 50 quid difference

[Agent]

36% ?, in which benchmark ?
Hit refresh on the benchmark and watch what happens, Sandra isnt that reliable.
Use a game or somthing that you will be using in the real world. Your not going to base which RAM you buy because Sandra shows an improvment.

[Rave]

If it was a synthetic memory bandwidth test you ran then you'll see a big difference running dual channel. In actual applications though, the extra bandwidth doesn't make much difference.

[madkez]

http://www.komplett.co.uk/k/ki.asp?sku=122785&s=sc

hmm is this stuff better than

http://www.scan.co.uk/Products/Produ...oductID=217959

i have decided that i can put up with the difference between cl2 and cl3 but whats the difference between these 2? i'm intending on running pretty much at stock 3500 venice speeds

[chinny]

36% ?, in which benchmark ?
Hit refresh on the benchmark and watch what happens, Sandra isnt that reliable.

OK - ran the same benchmark (Memory bandwidth benchmark) in Sandra 3 more times and give or take 10/15Mb/s or so get the same result. Results were single channel 2540Mb/s dual-channel 3661Mb/s (dual channel; result was actually higher on the other 3 runs).

Use a game or somthing that you will be using in the real world.

That's fair enough - am going to do some more benching and will post the results up.

Your not going to base which RAM you buy because Sandra shows an improvment.

I think you might have misunderstood me. I've accepted that CL3/2 won't make much difference. The thing is does dual channel - i.e. do I buy 2 x 1Gb sticks to maintain dual-channel or buy a single 1Gb stick and break the dual-channel? will that make a big difference.

[Agent]

I think you might have misunderstood me. I've accepted that CL3/2 won't make much difference. The thing is does dual channel - i.e. do I buy 2 x 1Gb sticks to maintain dual-channel or buy a single 1Gb stick and break the dual-channel? will that make a big difference.

I didnt mention CL2/3 ?

Dual channel will still opperate with 3 sticks btw. All it means is that one memory controler will have a higher load on than the other. Not really a big deal considering they never get near 100% usage in real-world anyway
You get the biggest gain by having sticks the same size and in pairs (2 or 4 slots), granted, but you will still gain from it.

[chinny]

Your not going to base which RAM you buy because Sandra shows an improvment.

Sorry if I'm being thick but could you clarify what you meant please.