GTX 660 overclocking

[ViperCDX]

Hi,using EVGA precision X i increased the power supply to the GPU by 10% and increased its core clock by 110 mhz(from 993 mhz to 1103 mhz),i didnot alter the voltage...
But games such as AC3 and FC3 crashes
Can any1 plz help

relevant info- mobo-gab75d3h,Cm elite 431 cabinet,crsair vs 550 psu

 

[timarp000]

If it crashes it means the card is unstable. to fix this you will have to reduce the clockspeed. from 1103 to 1098. If its still unstable go even lower by 5 till the game will play smoothly

 

[iam2thecrowe]

you cant change the voltage without a bios mod. What you will need to do is go here
http://www.xtremesystems.org/forums/showthread.php?284014-KGB-Kepler-BIOS-Editor-Unlocker
unlock more voltage, and higher 150% power limit.

 

[ViperCDX]

If it crashes it means the card is unstable. to fix this you will have to reduce the clockspeed. from 1103 to 1098. If its still unstable go even lower by 5 till the game will play smoothly

the game crashes after around 45-60 mins,dat means i have to reduce thye clock by 5mhz and play for at least 1 hour??
in furmark my gpu seems stable after watching for around 15-20 mins

 

[ViperCDX]

you cant change the voltage without a bios mod. What you will need to do is go here
http://www.xtremesystems.org/forums/showthread.php?284014-KGB-Kepler-BIOS-Editor-Unlocker
unlock more voltage, and higher 150% power limit.

i think u can also increase the voltage using EVGA precision X

 

[iam2thecrowe]

i think u can also increase the voltage using EVGA precision X

no. all that does is keep it at the maximum 1.175v "boost voltage" instead of dropping. these cards throttle up and down all the time depending on load, temperature, power consumption, they are a real ah heck to overclock and keep at a stable MHZ. I found it to be worse and more unstable with the latest driver release. the 310.70 drivers seem to be pretty good, stable, allow better overclocks than the newest 310.90. EVGA precision X was a pain in the arse for me, it looked pretty though. I found MSI afterburner more practical for monitoring your power, voltage and mhz stability, and offers the same overclocking performance.

Back at OP, have you checked if it crashes at stock clocks? I found the best test for me was 3dmark11. If i had an unstable overclock it pretty much crashed straight away in the "Graphics Test 1". I found ram on these cards to be overclocked by 300mhz quite easily, but as is usual in overclocking, dont increase too much at once. Start with 20mhz increase on the core clock, the 660 can get unstable very quickly. Work up to a point which is stable, then you can look at BIOS mod and overvolting to get more stability. I played around a bit with the bios mod and got 1230mhz stable at 1.1875v. Reading through some morums not many people have played around with voltage on these cards yet, but apparently the upper limit is 1.21v, but im going to wait for someone else to run it 24/7 at this voltage before calling it safe. Its fast enough for me as is anyway.

 

[ViperCDX]

no. all that does is keep it at the maximum 1.175v "boost voltage" instead of dropping. these cards throttle up and down all the time depending on load, temperature, power consumption, they are a real ah heck to overclock and keep at a stable MHZ. I found it to be worse and more unstable with the latest driver release. the 310.70 drivers seem to be pretty good, stable, allow better overclocks than the newest 310.90. EVGA precision X was a pain in the arse for me, it looked pretty though. I found MSI afterburner more practical for monitoring your power, voltage and mhz stability, and offers the same overclocking performance.

Back at OP, have you checked if it crashes at stock clocks? I found the best test for me was 3dmark11. If i had an unstable overclock it pretty much crashed straight away in the "Graphics Test 1". I found ram on these cards to be overclocked by 300mhz quite easily, but as is usual in overclocking, dont increase too much at once. Start with 20mhz increase on the core clock, the 660 can get unstable very quickly. Work up to a point which is stable, then you can look at BIOS mod and overvolting to get more stability. I played around a bit with the bios mod and got 1230mhz stable at 1.1875v. Reading through some morums not many people have played around with voltage on these cards yet, but apparently the upper limit is 1.21v, but im going to wait for someone else to run it 24/7 at this voltage before calling it safe. Its fast enough for me as is anyway.

oh,i did not know about that
yes,regarding 3dmark11--- why does it say my gpu clock is 549 mhz instead of ~1100 mhz and surprisingly the score DECREASES after overclocking,i have tried it many times but still getting the same results..
btw,it does not crash in any game at stock clocks and neither does it crash in 3dmark11 or furmark after overclocking

 

[iam2thecrowe]

the card throttles down at idle, so 3d mark reads idle clocks. you get worse performance when overclocking sometimes if the card gets to hot it throttles down, if it goes over the power limit it throttles. so increase fan speed and power limit. there is also a option in nvidia control panel to select performance mode "maximum" or "adaptive". adaptive is default, so change to maximum performance. Increasing your power limit in msi afterbuurner alone can help more than overclocking as the card can stay at boost clock for longer. OC'ing ram will be better for some games as ram never throttles. They are a tricky card to OC, and without bios mod are pretty limited.

 

[ViperCDX]

the card throttles down at idle, so 3d mark reads idle clocks. you get worse performance when overclocking sometimes if the card gets to hot it throttles down, if it goes over the power limit it throttles. so increase fan speed and power limit. there is also a option in nvidia control panel to select performance mode "maximum" or "adaptive". adaptive is default, so change to maximum performance. Increasing your power limit in msi afterbuurner alone can help more than overclocking as the card can stay at boost clock for longer. OC'ing ram will be better for some games as ram never throttles. They are a tricky card to OC, and without bios mod are pretty limited.

what to do,if i want 3dmark to read my boost clock??
the power is limited by EVGA precision X to 110%
do i have to change the performance mode maximum to every game in the control panel?

 

[iam2thecrowe]

I have 2 EVGA GTX 660 SCs OCed. You can't push these cards past +30Mhz on the gpu and + 400Mhz on the mem if you're lucky. They're limited by only having 1 pci-e connector as my cards' OC don't go past 73c.

my card never gets above 60c on 80% fan speed even when overclocked. and yes, you cant do much more than +30mhz stable without a BIOS mod to increase voltage and power limit.

 

[ViperCDX]

my card never gets above 60c on 80% fan speed even when overclocked. and yes, you cant do much more than +30mhz stable without a BIOS mod to increase voltage and power limit.

will there be any improvement by increasing the gpu clock just 30mhz??

and what is ur default gpu clock?

 

[iam2thecrowe]

^+1 oc the memory and increase power limit to keep the boost clock up. you can increase the gpu clock too, overall should give you a couple extra fps depending on game. I would say dont go strait away for +400 on the memory, might be unstable depending on the card, but +300 - 400 on memory is normally stable on these cards.

 

[timarp000]

I have a GTX 660 Ti. I got 1135MHz Boost and +300Mhz on memory

 

[Alex Whitfield]

Upon playing with it I found ways of performance gain mostly from the fan and power.
Go into the curve fan set it to 30% at 20c and increse of 10% per 10c until 60c once there make it jump to its full 80% allowance.
This will allow the card to push it self harder automatically.
5 - 10% gain in performance while running about 15 - 22celsius cooler on average compared to stock setting is what you should get out of this.
Than overclock ram by atleast 300mhz and give the gpu no greater than 50mhz boost.
Those two increases will actually hold less of an effect than the fan and power step but should force say another extra 2% performance out of the card all while still running atleast 10c cooler than stock settings.
If you wanna push further you HAVE to flash the bios to unlock full fan potential so you can keep things cool for your overclocking.
Remember there is only so much you can do seeing as this card is factory overcloked to begin with.
Best case scenario I got was about a 13% performance boost and averaging around 72c.
Achieved this with 100 mhz gpu oc and 1000mhz ram oc same fan settings except at 70 - 80c I have it jump its final 20% to keep from rising into the 80s and beyond. I am at 1.2 volts refuse to go further I don't wanna hurt my card.
I don't like pushing towards the 80s and I don't wanna turn voltage up higher as it would just tear down the card faster that way.
Solid card and a decent performance boost is achievable without killing the poor thing.