1900XT(X) OC points and more... (?)

[NightCrawler™]

I had massive issues clocking my XTX.. but after 30+ runs and losing my hearing I think I've found something which might help others.

My CPU ran comfortable and stable @ 2.6Ghz with 1.300 +110% vcore..
All tests were done with 3DM05 and after each test a reboot.. I had Everest logging my temps..

A stock run 648/775 gave me 11902 points...
Once I upped the core speed on the XTX I had random lockups during testing.. no matter what vcore I gave on the XTX it would still freeze even up to 1.500vc
To overcome that issue I had to raise my CPU vcore by 0.25v

Below are some runs all runs were done on 1.500 2.089 2.089 1.486 voltages and fan speed at 100%

702/775 12260
702/801 12385
684/801 12415

That was interesting which also triggered something I remembered from nVidia's 7800.. 27mhz per sweet spot..
So I calculated 648+27+27=702... not gonna work as 702 gave me a lower score then 684... so the sweet spot had to be different then 27mhz.
684 worked great.. which is exactly 36Mhz more then stock... sweet spot...?

With that in my mind 720 would be the next sweet spot (684+36) so I set AtiTool up with 720/801 and ran 3DM05.. which failed.. so I upped the GPU vcore to 1.525...
Again 3DM05 failed but it took the 2nd test for it to fail... hmmm... So I upped my CPU vcore with another 0.25v to 1.350 +110% and ran 05 again...
This time it would pass just fine with a very nice score too.. 12660

So in short... I believe every 36Mhz from 648Mhz is a sweet spot... this needs to be confirmed by other XTX owners though..
If your bench freezes.. up your CPU vcore by 0.25v.. as it makes a difference for some reason...
Chances are this will also work for the XT....

I hope this helps others in OC'ing their XT(X) :toast:

[Winterwind]

i get only 10.6k with my XTX and 4ghz Presler in 3dmark 2005..
and 4500mhz it scores 11,5k with vga default..
it is kinda low isint it?:(
4ghz and XTX @ def 06 score is 6k and bit over but that 05 is killing me

[einCe]

ill be able to test this for you once i get my rig back up and running.

[NightCrawler™]

Your sig says it all.... :(

[Trice]

How does raising the CPU do anything? Sounds like your PSU is quirky.

[einCe]

Your sig says it all.... :(
hehe yeah i know, shouldnt be too long

[cantankerous]

nice find, I am glad your finally getting some positive results too. I have my core at 685 and I too find it a sweet spot for my XTX. I have ram running at 810 while the core is at 685 and all this is with 1.400v on the core and stock ram volts. I find trying to go any higher than this also causes lockups or VPU recovered solid black screens causing me to force a reboot of the system to get back up and running. I find I can still clock my ram higher however at same volts as long as my core doesn't increase in speed. If I lower my memory speed I am sure I can go higher on the core. What I am wondering is what would grant me better performance 685 core with higher early 800's on the mem stable or lower late 700's on the ram with early 700's on the core. Heat is a major concern however and I find 1.400v and 685 very reasonable with temps never exceeding the mid 70's under full load which is fine by me. If I left vcore at stock, lowered my ram speed but raised my core speed would temps still go up even though I am balancing it out with lower mem speeds? Everything runs great at what it is. My CPU is a single core that can do a max of 2.48ghz with 225 on the mem controller max. With this I hit about 11.2k in 05.

[einCe]

from what ive seen higher ram clock nets more performance as long as the core is qaround 650-80

[PkG.1337]

684 + 36 = 720
720 is another sweet spot?
i m ganna try that out now
1900xt crossfire water cooled

[GoThr3k]

will try once i am back from vacation mate

[perkam]

I had massive issues clocking my XTX.. but after 30+ runs and losing my hearing I think I've found something which might help others.

My CPU ran comfortable and stable @ 2.6Ghz with 1.300 +110% vcore..
All tests were done with 3DM05 and after each test a reboot.. I had Everest logging my temps..

A stock run 648/775 gave me 11902 points...
Once I upped the core speed on the XTX I had random lockups during testing.. no matter what vcore I gave on the XTX it would still freeze even up to 1.500vc
To overcome that issue I had to raise my CPU vcore by 0.25v

Below are some runs all runs were done on 1.500 2.089 2.089 1.486 voltages and fan speed at 100%

702/775 12260
702/801 12385
684/801 12415

That was interesting which also triggered something I remembered from nVidia's 7800.. 27mhz per sweet spot..
So I calculated 648+27+27=702... not gonna work as 702 gave me a lower score then 684... so the sweet spot had to be different then 27mhz.
684 worked great.. which is exactly 36Mhz more then stock... sweet spot...?

With that in my mind 720 would be the next sweet spot (684+36) so I set AtiTool up with 720/801 and ran 3DM05.. which failed.. so I upped the GPU vcore to 1.525...
Again 3DM05 failed but it took the 2nd test for it to fail... hmmm... So I upped my CPU vcore with another 0.25v to 1.350 +110% and ran 05 again...
This time it would pass just fine with a very nice score too.. 12660

So in short... I believe every 36Mhz from 648Mhz is a sweet spot... this needs to be confirmed by other XTX owners though..
If your bench freezes.. up your CPU vcore by 0.25v.. as it makes a difference for some reason...
Chances are this will also work for the XT....

I hope this helps others in OC'ing their XT(X) :toast:
Maybe now we know there was a reason why ccc was limiting OCs to 690/800 ;)

Perkam

[cantankerous]

from what ive seen higher ram clock nets more performance as long as the core is qaround 650-80

Thanks for the response, I was afraid my question was going to get barried in my babble and I would never get a response. With my core at 685 I am definately within the range you noted so that is a great thing. I am sure I can go higher on the ram without having to raise vcore so that is a great thing. The fact that I should net more performance this way is even better. I guess this is why the R580+ would benefit from GDDR4 ram due to the higher bandwidth those chips can produce.

thanks again.

[PkG.1337]

700/800 is higher by 100 points in 3Dmark06 over 684/800
X1900XT Crossfire Enabled
6.6 offical

no luck for my CF setup
more testing tonight

[dexx]

I found another interesting thing when using ATItool.
If i boot my xtx stock i score 12200 in 3dmark05. If i load atitool and adjust the volts and clock, then adjust them back to stock and do an 05 run, i score only 11800. I have to boost atitool to 684/702 to get the same score i had with a fresh boot! Looks like atitool screws with memory timings or somesuch.

[Frackal]

I've never had much luck with ATI Tool so far in my XTX OCing experience, either with the one I borrowed or the one I bought.

[NightCrawler™]

I think AtiTool also adjust the memory timings which give people a lower score then without...

[Trice]

Youre thinking of the other overclocking tool

[NightCrawler™]

Rivatuner....?

After some more testing an fiddling with settings.. I'm convinced it has to do with the 9Mhz jump.
nVidia used 3x9=27Mhz per sweet spot Ati does 4x9=36Mhz... however I think once the core goes beyond it's first sweet spot it needs something else to make a similar jump in scores..
From 648 (11902) to 684 (12415) yields in 513 point gain... however going from 684 to it's next spot 720 (12660) only gains 245 points...
That's only half of what you get with it's first spot... Maybe that's were VDDCI comes into play but I need to test that one out...

[STEvil]

rivatuner does not adjust timings unless you enable it in the power user options... and I think thats only available in the latest beta (not publicly released yet).

[NightCrawler™]

The one thing that's still doing my head is why I had to increase my CPU voltage to increase my GPU core speed.. It just doesn't make any sense to me..

[Counter CS]

Nice too reade this thread, now here is my score at 690/800Mhz and X2 3800+ @ 2970Mhz :D

http://img117.imageshack.us/img117/7659/ocz2707pv.jpg

[NightCrawler™]

What does the score for you if you set it @ 693Mhz....?

[NightCrawler™]

Alright.. I did some more testing I raised VDDCI to 1.510 which improved my scores a bit.. So raising it does aid to getting better scores..

I also noticed another thing which I strike as odd... when using the card @ stock and stock fan control I can see temps go above 80°C with ease.. and give me no issues at all..
The first run I did with the increased VDDCI I used manual fan controlled settings where the fan would spin up to 100% if temps reached 80°C
During the run it froze quite fast.. after setting the fan speed to 100% all the time the run was completed... So it seems when you're OC'ing the XTX your temps need to stay well below 80°C or it will simply lock up...

I ran 3DM05 with 720/801 1.525 2.089 2.089 1.510 and got a 12716 score..

http://img240.imageshack.us/img240/5263/3dm05127160ch.th.jpg (http://img240.imageshack.us/my.php?image=3dm05127160ch.jpg)

I think I can give it more but my RAM is getting rather hot already... ~ same temps as the core so a bit on the high side.
Another thing is my CPU speed is holding me back... but 2.6Ghz is the max it will do on air 24/7...

[Viss]

OC tool (http://www.xtremesystems.org/forums/showpost.php?p=1485587&postcount=12) does loosen mem timings, atitool and riva dont (at least in me case with X1800XT).

[dexx]

My XTX is behaving in a similarly strange way. At stock clocks (648/774) on my Opteron @ 2.4 i get 10973 in 3dmark05. Using ATItool, 685/774 gets me 10875. 685/800 gives 10922. 702/800 gets 10985 and 720/820 gets 11113. So it seems like overclocking, in my case, give hardly any performance benefit at all. :(

[ahmad]

Don't open 3dview at all when OCing with ATItool.