Corsair 2GB Kit SPD Settings

[jonathan_phang]

Hello all,

just purchased and installed the following memory:

http://www.scan.co.uk/Products/Produ...oductID=291360

Now, the timing for this memory are meant to be 3-4-4-8. My Opteron is currently running at 250x10, so it thought that it may be good to run the memory at 250mHz too, so that i get the most bandwidth. However, after installing and running CPU-Z, the following was there:

Cas# Latency: 2.5 Clocks
RAS# to CAS# Delay: 3
RAS# Precharge: 3
Cycle Time (Tras): 8 Clocks
Bank Cycle Time (Trc): 11 Clocks
DRAM Idle Timer: 16 Clocks

Now I dont really know too much about the timings side of overclocking and tend to just use SPD settings, but do the above mean that the mobo has detected the wrong settings? If that is true, do i just adjust the values accordingly so that in CPU-Z it would be:

Cas# Latency: 3.0 Clocks
RAS# to CAS# Delay: 4
RAS# Precharge: 4
Cycle Time (Tras): 8 Clocks
Bank Cycle Time (Trc): 11 Clocks
DRAM Idle Timer: 16 Clocks

I only ask because if you run them at 250mHz then i dont want to risk instability by running them at tighter timings than specified (not at least until i KNOW they are fine and stable at stock).

Any help would be much appreciated.

JP

[teachmech]

Are you currently running them a 200? If so then that is why the timmings are slighlt tighter, when you run at 250 then the timmings should got to the advertised.

[jonathan_phang]

No, currently, I am running the CPU with a 250 HTT and a 10x Multi. However, you have raised a point, with my old ram which was Kingston 3500, i had to run with a 166/200 divider, which is basically running the ram at 250 x 0.83 = 207mhz.

When I dropped the new RAM in, I left the divider as it was, just to make sure that if it wasnt stable then i could isolate it as just the ram being the problem. So you think that the SPD settings (what is detected by Auto) is changed because of the divider?

Maybe i wil try later to see what the mobo detects if i run the mem without a divider. Either way the question is still valid - are the settings that are shown in the first post the same order as the timings quoted? 3-4-4-8?

If so then i can just change it in the BIOS right?

JP

[teachmech]

The timmings show are slighlty better than those quoted as the ram is running slower than the advertised speed of 250. So when you remove the divider and run the ram at 250 the timmings will run as advertised.

[jonathan_phang]

Cheers for the advice, will try that out later on tonight!

[jonathan_phang]

Noooo!!

Tried it out at 250HTT and witht the 200 divided (which is 1:1) and the computer wouldnt boot. Gave me a massive fright, wasnt even getting to POST and usually 3 failed posts resets my mobo to default settings, but nothing, I even got some strange message on the screen about the X1800XT, so i thought i had killed it! But I put in my old ram, cleared the CMOS and then went in and put my settings as they were with a 166 divider. Then plonked the 2GB back in and its fine running at 207 (250*(166/200)). Seems odd as the HTT has always been fine, so the RAM should cope fine as that is its rated speed. I thought that it may be a voltage thing, but in reviews it stated that it only needs 2.6v to run and thats standard on my board.

Strange, and rather worrying as i bought the 2gb kit to maximise the memory bandwidth being used - i really dont want to start testing BIOS settings again as i have been pretty stable for a while now, but it might be the only way...

Any comments to help my situation would be great

JP

[jonathan_phang]

Double Post

[NightshadowUK]

Try setting everything to do with memory on 'Auto'.

[jonathan_phang]

I did, and thats how i noticed that the SPD settings were low. However, after one of the points above it seems like the SPD may have tightened the timings due to running at a lower mem frequency.

As per my other post I cant get them to run at 250 (and i had everything set to auto for the switch to 250HTT) but on the following link:

http://www.xbitlabs.com/articles/mem...roundup_5.html

I think that it states the timings are 3-4-4-10?? Maybe I have to set these manually in the BIOS before the RAM will work. Theres that and then maybe the voltage - i could put it to "high" on my mobo, which is effectively 2.7v and maybe that may help.

OR I could just be happy with 207mhz and get on with playing Oblivion....

[GoNz0]

quite a lot of corsairs ratings have to be set manually, along with the 2.7V for stability, the SPD is the basic spec for the stick as per JEDEC standards.
its up to you, if you like it how it is leave it alone

otherwise put them to spec and up the ram voltage to 2.7.

[jonathan_phang]

Well, I would LIKE it to run as rated, but i dont want to have to open up my computer, swap ram in/out etc like last time...I'm not the only one who uses the computer as My old man relies on it for business - despite it being mine! - so i guess i can wait, but i just want to make sure they arent duff sticks etc.

I think that i may lower the HTT to 200 and manually put the sticks to the required settings. I may try 3-4-4-10 as that article seemed to indicate that would be needed for 250, but then i will try to post and up the HTT by 10 if successful... Who would have thought it was going to be this difficult!!!

[-ChEM-]

make sure youve got it set to 2T (something like "command per clock = disabled"), you need to with asrocks

[jonathan_phang]

Yeah - As an update, I put the ram to 3-4-4-10 and then put the voltage to "High" which equates to 2.7 on my mobo. Then tried to boot from 200HTT increasing 10 each time. And the end of it all is that it now runs fine at 250... I already had it at 2T because there is an issue with odd restarts with T1 (With this Asrock Board in general, not just mine), but i dont think that theres THAT much difference in actual game play.

..Next to update my BIOS to get rid of the 274HTT lock and then try and get my Opty to about 2600 or 2700 stable.

But i think that i will actually PLAY oblivion first, instead of buying bits for it and tweaking the engine all the time. I swear i configure it more than playing it

Still, i think that its a bit naff that its advertised as 3-4-4-8 when its not going to run unless you manually set the timing different...But alls well that ends well...

[-ChEM-]

Still, i think that its a bit naff that its advertised as 3-4-4-8 when its not going to run unless you manually set the timing different

isnt that a good thing as long as it works?

[kalniel]

Well it should auto set to the SPD rating advertised, but it quite commonly doesn't (EPP will help with this).

On my board I just have to set the CAS to 2 manually, but once I do that all the other ratings match SPD on auto (2-3-2-5).

[jonathan_phang]

isnt that a good thing as long as it works?

Well, no, not really. If there is a pre-requisite to have the timings at 3-4-4-10 to run at the rated speed then it should either be hard coded. which is what i though SPD was for, for at least documented.

Maybe its just an issue with my mobo, but if i buy 500mHz ram i expect it to run if i set HTT to 250 when i drop it in. Otherwise it could have been stated that those specific timings were needed. Its not hard to change, but it was pretty inconvenient if you dont know that you have to do it.

Anyway no major trauma anymore, but i wasnt impressed. RAM itself is good though...