Memory Timings Know how??

UNhooked · § #1 06-18-2003, 07:45 PM

hi can someone kindly explain me how to use max memory timings? I keep seeing people saying that they are running at 6-2-2-2 what does it all mean. As in I know that they are timings, but to what respectively.

Currently i am running Cas 2.0 Tras 3 TRcd 2 TRp 2
so how do i max the timings or tweak it to acheive max performance??

currently on Soltek 75rn at 211X11 but yet i get a Sisoft score only of 3165Mb/s and people with lower FSB are getting a lot higher so what am i doing wrong??
thank you

Viola · § #2 06-18-2003, 08:12 PM

Hrm your score is very good, I don't know why others would be getting higher. Your timings are already very tight (which means lower, which means faster but more likely to cause instability if you've pushed too far on FSB). The big one is the cas 2.0, that gives you the most benefit.

The "tightest" I've seen is radiohead's 5-2-2-2 which means Tras 5, Ras precharge 2, Ras to Cas delay 2, and cas latency 2.0. I am currently running 6-3-3-2 as my memory isn't quite as high end, so these are the timings it likes.

I'm not sure how much performance difference you get for the numbers besides cas 2.0, but between cas 2.0 and cas 2.5 there is a noticeable difference in game performance.

One thing I don't see on the FRN2 is command rate, so maybe that's no longer an adjustable thing.

Bianca

MoodyB · § #3 06-18-2003, 08:30 PM

The odd thing is that lower settings can be slower on the NF2 chipset for some reason. If you bench at 5-2-2-2, I'll bet that 6-2-2-2 is faster.

Try raising your timings slightly to 6-2-2-2 and see what you get.

**Radiohead** · § #4 06-18-2003, 09:00 PM

MoodyB is right. I am currently running my OCZ Dual Channel Enhanced Latency PC 3500 at 6-2-2-2 and my memory throughput is greater at these settings than 5-2-2-2. I have actually seen mention here in the Soltek Forum of someone running 4-2-2-2.
As Viola says the nforce chipset does not include a command rate setting, I'm not even sure if it adjustable with the NF2 memory controller perhaps because there are two controllers, I'm not sure.
Some makers are actually programming preferred settings into small chips on the RAM sticks themselves which actually by what I've heard have to be entered into the bios in order to have the memory function at all. I feel I encountered this with my first early release FRN-L which if pushed to far required me pull the OCZ then insert some Micron 2100 RAM to get the system back up and running at which point I could reset the bios to optimal settings at which point the bios would recognise and run the mem at 400mhz and the fsb at the chip default of 133 (async). I could upon the next reboot adjust my memory timings back to 5-2-2-2. With the FRN2 I feel a bit more secure in the bios and have experimened with the settings but remain very conservative with making any more than 1 or 2 changes between boots. Not sure if what I just said makes any sense or is even remotely right but I hope it helps. If anyone has a better understanding of the NF2 mem controller please chip in here.
A very good rule of thumb is this generally. The lower the number, the faster the timings.
Anyone who claims to be getting higher scores than you ie 3165 is doing very well indeed. Some memory seems to mesh better with the NF2 controller than others if thats the case. My throughput is currently 3100 flat with a 200FSB in Sisoft Pro 2003 with Norton AV, HWM and Rage3d tweak running in the sys tray. If all these things are disabled then my throughput (bandwidth) would rise a few points (10 at the most). The higher the FSB the faster the data tavels through the memory. There are lots of good explanations with regards to Cas Tras etc available for the reading. Seems to me Corsair has some pretty good data on the subject and would most likely explain it better than I could.

missylainey · § #5 06-18-2003, 09:08 PM

look here :

http://www.amdforums.com/showthread....hreadid=229654

there`s a fella here says 9-2-2-2 or even 11-2-2-2 is faster than 5 or 6-2-2-2 .... don`t know how ... but I`d like to know if anybody can explain ... keep thinking I`ll try it but not sure if my bios will allow that ...

IMO 5-2-2-2 seems better on my DRV5 than 6-2-2-2

**Radiohead** · § #6 06-18-2003, 09:16 PM

5-2-2-2 was certainly faster on the 266A chipset boards and the 333 chipset boards as well. I think there is still a lot we don't understand about the dual channel memory controller.

TheOtherDude · § #7 06-18-2003, 10:36 PM

This link should explain it all.

**Radiohead** · § #8 06-18-2003, 11:53 PM

Thanks otherdude. Good link, very informative. When using older versions of Sisoft Sandra on my DRV2 it used to specifically list the name and precise settings of the memory modules and the Command rate also I think. I know for sure the command rate used to be displayed on my AMD chipset Gig GA7DXR right down to the letter. I wonder if it still does with the intel setups. Be interesting to find out.

Mr Sinister · § #9 06-19-2003, 03:07 AM

Great link dude.

Im trying to convert the ram options I have in the BIOS of my DRV5 into the 6-2-2-2 model. ie tras=dram burst length???

I thought i had it worked out but some of the options dont give figures that fit into the model

I have these options in my BIOS:
Dram Cas Latency: im fine with this one
Bank Interleave:??
Dram Burst Length:??
Dram Queue Depth:??
Also has command rate and system performance options but i dont think these apply when people state their ram settings as 6-2-2-2

Any help would be great.
Thanks

TheOtherDude · § #10 06-19-2003, 03:17 AM

Quote:

Originally posted by Mr Sinister
Great link dude.

Im trying to convert the ram options I have in the BIOS of my DRV5 into the 6-2-2-2 model. ie tras=dram burst length???

I thought i had it worked out but some of the options dont give figures that fit into the model
I have these options in my BIOS:
Dram Cas Latency: im fine with this one
Bank Interleave:??
Dram Burst Length:??
Dram Queue Depth:??
Also has command rate and system performance options but i dont think these apply when people state their ram settings as 6-2-2-2

Any help would be great.
Thanks

Bank Interleave: 4 Bank
DRAM Burst Lenth: 8
DRAM Queue Depth: 2 (Not significant to performance)
Command Rate: 1T
System Performance: Fastest

The "system performance" setting when set to "Fastest" will run 5 (tRAS)-2 (tRCD)-2 (tRP) and you already set the CAS to 2. This puts you at 5-2-2-2. Don't know why, but Soltek won't allow you to run 6-2-2-2. I also wonder if the info in that link is entirely and universally true. Why would Soltek allow 5-2-2-2 instead of 6-2-2-2 if the later was faster? Hum. Puzzling.

}EDIT{ After consulting my DRV5, I made some changes to my suggestions.

Viola · § #11 06-19-2003, 03:18 AM

Oh I forgot you were working on drv5, I was talking nforce2 frn2 numbers.

Well let's start with easy ones, bank interleave should be at 4. Leave it at 4.

Command rate can be either 1T or 2T. 2T is default and the "loose" timing. I would adjust that number ONLY after you have all the other numbers stable and working at the FSB you want... then and only then attempt command 1T. I believe the other numbers can be either 3 and 3 or 2 and 2. Try both and see how it works. Use sisoft SANDRA to do quick benching of how it's working, to see if you gain anything. If you don't gain any bandwidth from tightening a setting, there's no reason to tighten it. Er at least I think, maybe latency improves, hrm .

Do you have CPU-Z? That's the program I think most people use to come up with the list "6-3-3-2" that you hear. Google for cpu-z and download it, extract it, run it, and you should get 4 numbers. I don't think command rate is included.

Hope that helps a little,
Bianca

TheOtherDude · § #12 06-19-2003, 03:22 AM

Quote:

Er at least I think, maybe latency improves, hrm .

If all he changes is his timings, and bandwith doesn't improve, then latency doesn't improve.

MoodyB · § #13 06-19-2003, 08:46 AM

Quote:

Originally posted by missylainey

there`s a fella here says 9-2-2-2 or even 11-2-2-2 is faster than 5 or 6-2-2-2 .... don`t know how ... but I`d like to know if anybody can explain ... keep thinking I`ll try it but not sure if my bios will allow that ...

IMO 5-2-2-2 seems better on my DRV5 than 6-2-2-2

I cant explain it, but at the XtremeSystems forum, there's a thread somewhere, that on the NForce2 chipset at least, that a t(ras) ? of 14 produced the fastest results with 7 being the 2nd fastest...

TheOtherDude · § #14 06-19-2003, 12:03 PM

Quote:

Originally posted by missylainey
look here :

http://www.amdforums.com/showthread....hreadid=229654

there`s a fella here says 9-2-2-2 or even 11-2-2-2 is faster than 5 or 6-2-2-2 .... don`t know how ... but I`d like to know if anybody can explain ... keep thinking I`ll try it but not sure if my bios will allow that ...

IMO 5-2-2-2 seems better on my DRV5 than 6-2-2-2

I find 11-2-2-2 to work best for me. In case anyone thinks it might have something to do with dual channel, I tested in both single and dual channel modes and found 11-2-2-2 to be the best in both. Weird.....

Mr Sinister · § #15 06-19-2003, 06:45 PM

Thanks for all your help. Ill download CPU-Z and see exactly what im running.
At the moment im running with the system performance at normal. Running faster than this causes massive instability.
Ill change it to cas 2.5 and up the voltage and see if the stability improves. Through playing with my ram settings ive finally broken the 13000 barrier in 3Dmark2001SE. :P

Thanks again.