Trying to dip into the 25's...i'm stuck!

[Ator]

Hey everyone!

I've gotten the hang of A64 Tweaker, and I now know what timings will affect stability and such. With the recent purchase of a CAB2E 0540FPMW Opteron 146, i've been having fun with SuperPI 1M.

Yes, I finally broke 3200Mhz on AIR! I'm sure most of you Opty OC'ers have already done this, but i'm damn happy with it.

At any rate, i'm really struggling to get it stable enough to run above this. I've tweaked the voltages, experimented with timings, DQS Skew, etc...nothing seems to work. I can use ClockGen to go far above 3200Mhz (I did 3230 just messing around), but it just won't work above 3200!

So, i'm asking you guys, what do I need to tweak to get it to run above 3200? Running 2T doesn't help stability, and neither does a lower CPU multiplier + higher FSB, or stock multi + RAM divider. It seems that it REALLY wants me to toy with the DQS Skew when I go above 3170Mhz. Timings are as tight as it'll allow me to go right now.

Thanks guys! You all inspire me to OC more and more every day.

[Zeus]

You won't need over 3,2GHz to go sub 26 seconds.

http://img.photobucket.com/albums/v620/Z3us/SuperPifactory/SPi1M25sec.jpg

Running 2T kills performance, don't do it.

All you need is a clean install, kill some services and tweak your RAM to the max.

GL ;)

[metro.cl]

i believe that is your cpu limit if you are on air, try water or single stage

[mcnbns]

Get rid of your desktop image to free up a bit of RAM.

Get rid of the crazy Luna theme and go for Windows Classic.

Drop into msconfig (Run, "msconfig") then go into the General tab and reboot in Diagnostic mode for more dead services than you can shake a stick at.

You've probably already done the Real-time task manager process priority and stuff like that, so I won't insult you any more by suggesting things.

Bonne chance! :toast:

EDIT: Are TRC and TRFC as tight as they'll go? I know you said thats as tight as it gets, but that looks really loose...

[afireinside]

The trfc and ESPECIALLY the trc are killing your performance. Big time. 3.2ghz is damn good for air. You probably won't get any more out of the chip. Drop a lower divider and run tighter trfc/trc. Pi loves tight timings.

[Zeus]

Agreed, timings are horrible.
Better timings will net you 25 seconds, getting more out of that chip is highly unlikely on air.

[before]

Zeus is right; you can go sub 26s with a clock lower than 3.2GHz

http://www.beforeoverclock.com/images/CABCE0516WPMWSUPERPI1M25s.jpg

I guess your TCCD might be able to run with better timings; drop a lower divider if required...

[dinos22]

how much have you tweaked the OS and registry

what hard drives are you using

i would try running 2.5-3-3-6 1T on divider as SuperPI likes tighter timings

if you want to continue with those 1:1 speeds try these

DQS....go back to default

TREF timing is ok but i'd also try 133/166 1.95us

TRC/TRFC too loose try using 7/14
use TRAS =8
TWR/TWTR=2
TRTW=3
you should be able to run MAL=9,RP=6 comfortanly at 320MHz HTT
Idle Cycle Limit.....play with 16/256 and see what happens

what data/drive strength are you using.....? What is your RAM voltage.....you may need to experiment with weaker values in case you experience stability issues with tighter timings.....higher vdimm will probably put more pressure on stronger drive/data strenght.....there seems to be a relationship between MAL & drive/data strenght



but the best thing to do first is go with lower MHz on RAM and tighter timings trust me...........see if you can run at 291MHz 2.5-3-3-6 1T with 183 divider :toast:

also BH5 ram will give you more joy in SuperPI

[Ator]

I really can't set the timings any tighter...if I set the Tras to 9, it'll BSOD. Same with any of the other timings. I just think my TCCD sucks or something.

Drive Strength: 8
Data Drive Strength: 3 (or Auto, don't remember; anything else would make things wayy worse)

1.95us refreshes slowed it down significantly, same with increasing idle cycle timer. It seemed to like 4, so I stuck with it.

DQS is what got me to 3200 in the first place. ;)

TRC/TRFC would NOT run that tight even at 300Mhz.

I could tighten the TRTW, etc...just did that for stability reasons.

Async Latency and Read Preamble were a biotch to tune...again 11 and 7.5 were the sweet spot. Nothing else seemed to work, altough i'm running 8 and 5 right now @ DDR600 with no problems. I may give it another shot when I get some sweet air again.

That "diagnostic mode" and the other Windows tweaks made no difference with times, just more of a hassle. That's why I didn't do that. 26.102 and 26.109 wouldn't be worth it IMO.

Thanks for all the tips, i'll give them a shot as soon as it cools down here again!

[dinos22]

drop your divider and shoot for 2.5-3-3-6

[corvus_corax]

Yes, you can hit sub 26swith lower clocks, for example with 3.1GHz ;)
http://img59.imageshack.us/img59/5026/op146310258gsshsp1m3jn.png

It seems to be like you have reach your max on air. But sometimes, playing with Drive Strength and Data drive help, you can try with Drive Strength=7 and Data Drive Strength: 1 or 2.

[Ator]

Hey guys, just a quick update.

It just isn't cold enough around here to get high clocks. I was lucky I guess when I got 3200Mhz...The highest I can hit now is 3170Mhz, and with a 5:6 divider, my 1M times were sucking. I was ~0.5sec off at least, if I remember correctly.

I'll just have to wait for my next paycheck, and pick up a full DangerDen watercooling setup.

Thanks again for the help, though. I tried out some of the Async Lat. and Preamble tweaks, along with dropping the Trc and the Trfc, and those helped, until I started getting "Not exact in round" and repeated BSOD's.

[Zeus]

Mess around with Dram drive strenght and data strength, this will regain your stability.