Do 1gb sticks ALWAYS have a higher CAS latency as opposed to 512's?

[DragonMasterAlex]

I'm eyeballing some new RAM, and I'm torn between 1gb sticks or 512MB dual channel sticks. Either way I will get dual channel, but I want 2 gigs worth of memory. I've read that a lot of 4 slot boards get unstable with 4 slots all populated, which leads me to want dual 1gb sticks instead of 4 512's. On the other hand, the 1gb sticks I see all have Cas 3 or higher, whereas the 512's are 2-2.5 for good memory.

Anyone have any good advice on this area? I'm eyeballing geil PC3200 right now, as well as an Athlon64 setup, but I really want to be sure I don't blow it

Thanks!

Jason

 

[Promethply]

Yeah, you're quite right about the CAS latencies in general, since RAM manufacturers are concentrating more on selling the 512 sticks,

But Corsair does make a CAS 2 1024 Stick RAM that works @ 2-3-3-6 on Intel systems, but works only @ 2.5-3-3-6 on the AMD64 system:

Corsair TWINX MATCHED MEMORY PAIRS

 

[Concillian]

It's more difficult to make the higher density chips at CAS2, so you don't see them nearly as available.

I don't think any tests have been done, but I would think 2x1GB even at higher latency would be better than 4x512 and the 2T command rate necessary to make them stable.

 

[Promethply]

Actually in real life, you won't notice much difference at all whether using CAS2 or CAS2.5, except when you're benchmarking your system.

The RAM setting that makes the most difference in an AMD64 system is the 1T/2T timing: Your system's memory performs much better on the 1T timing.

Now if you populate all 4 DIMM slots, with the current AMD64 CPUs, your timing can only be set at 2T, but this may change with the Venice cored CPU.

 

[GuitarDaddy]

OCZ and Kingston both now make CAS2 1024 modules. But bend over and grit your teeth, they sell for around $700 for a 2gb kit

 

[mamisano]

Just went from 4x512MB Cas 2.5 sticks to 2x1GB Cas 3 sticks. Same performance according to Sandra.

 

[DragonMasterAlex]

Originally posted by: GuitarDaddy
OCZ and Kingston both now make CAS2 1024 modules. But bend over and grit your teeth, they sell for around $700 for a 2gb kit

Yikes, does it come with a free jar of vaseline? Yeesh!

Jason

 

[DragonMasterAlex]

Originally posted by: mamisano
Just went from 4x512MB Cas 2.5 sticks to 2x1GB Cas 3 sticks. Same performance according to Sandra.

Interesting. Well poop; if it comes down to that I might as well use 1 gig sticks, since that way at least I have the option of adding more capacity later on.

Thanks, guys!

Jason

 

[DAPUNISHER]

SiSuck should not be used to compare performance, unless it is the only thing you do with your system

You will likely never notice the difference between CAS 2.5 and CAS 2 unless you are a benchmark ho either.