Flickering and DPC Latency
Originally with an 8800 GTS everything worked perfectly for me. After installing a GTX 295 I had horrible flickering (several times per second.) After a lot of trying I was able to get to the point of no flickering. My machine is a Q6700 running at 2.66 GHz on a P35 with 8GB of 800 MHz memory. I'm running Vista 64.

I had ghosted my machine before I started reinstalling drivers and got everything happy. So I reverted back tonight to try and see what was different. As expected, my machine went back to flickering madly.

I noticed something with my delayed procedure call latency so I ran a test. With the a clean install of CD 1.04 drivers and playing WoW my DPC latency stays consistently below 1 ms. When I install the CD 1.05 beta drivers over top of this my DPC latency ranges from 3 to 4 ms. I overclocked my processor to 3.2 GHz and it may have been slightly lower but it was basically no change. I forced my USB to 1.1 with no change.

I then started WoW and toggled the 3D Vision on and off. While 3D Vision was on I was at about 3-4 ms and when 3D Vision was off my latency was about 250 us. A significant difference.

I then took my clean 1.04 install and installed the WHQL 182.06 drivers without updating the 3d vision drivers. The result was the same.

I assume the IR transmitter is a time critical device and latency has to be kept to a minimum for it to function properly.

I went through and disabled every piece of hardware I could (without blue screening) and it appears as though it is the graphics driver alone that is killing my performance. But only when WoW is full screen with the 3D turned on.

Does anyone else with flickering issues see the same result? Specifically do you see higher than normal DPC latency while the 3D transmitter is engaged?
Originally with an 8800 GTS everything worked perfectly for me. After installing a GTX 295 I had horrible flickering (several times per second.) After a lot of trying I was able to get to the point of no flickering. My machine is a Q6700 running at 2.66 GHz on a P35 with 8GB of 800 MHz memory. I'm running Vista 64.



I had ghosted my machine before I started reinstalling drivers and got everything happy. So I reverted back tonight to try and see what was different. As expected, my machine went back to flickering madly.



I noticed something with my delayed procedure call latency so I ran a test. With the a clean install of CD 1.04 drivers and playing WoW my DPC latency stays consistently below 1 ms. When I install the CD 1.05 beta drivers over top of this my DPC latency ranges from 3 to 4 ms. I overclocked my processor to 3.2 GHz and it may have been slightly lower but it was basically no change. I forced my USB to 1.1 with no change.



I then started WoW and toggled the 3D Vision on and off. While 3D Vision was on I was at about 3-4 ms and when 3D Vision was off my latency was about 250 us. A significant difference.



I then took my clean 1.04 install and installed the WHQL 182.06 drivers without updating the 3d vision drivers. The result was the same.



I assume the IR transmitter is a time critical device and latency has to be kept to a minimum for it to function properly.



I went through and disabled every piece of hardware I could (without blue screening) and it appears as though it is the graphics driver alone that is killing my performance. But only when WoW is full screen with the 3D turned on.



Does anyone else with flickering issues see the same result? Specifically do you see higher than normal DPC latency while the 3D transmitter is engaged?

#1
Posted 02/21/2009 08:55 AM   
[quote name='enyar' post='508647' date='Feb 21 2009, 04:55 AM']Originally with an 8800 GTS everything worked perfectly for me. After installing a GTX 295 I had horrible flickering (several times per second.) After a lot of trying I was able to get to the point of no flickering. My machine is a Q6700 running at 2.66 GHz on a P35 with 8GB of 800 MHz memory. I'm running Vista 64.

I had ghosted my machine before I started reinstalling drivers and got everything happy. So I reverted back tonight to try and see what was different. As expected, my machine went back to flickering madly.

I noticed something with my delayed procedure call latency so I ran a test. With the a clean install of CD 1.04 drivers and playing WoW my DPC latency stays consistently below 1 ms. When I install the CD 1.05 beta drivers over top of this my DPC latency ranges from 3 to 4 ms. I overclocked my processor to 3.2 GHz and it may have been slightly lower but it was basically no change. I forced my USB to 1.1 with no change.

I then started WoW and toggled the 3D Vision on and off. While 3D Vision was on I was at about 3-4 ms and when 3D Vision was off my latency was about 250 us. A significant difference.

I then took my clean 1.04 install and installed the WHQL 182.06 drivers without updating the 3d vision drivers. The result was the same.

I assume the IR transmitter is a time critical device and latency has to be kept to a minimum for it to function properly.

I went through and disabled every piece of hardware I could (without blue screening) and it appears as though it is the graphics driver alone that is killing my performance. But only when WoW is full screen with the 3D turned on.

Does anyone else with flickering issues see the same result? Specifically do you see higher than normal DPC latency while the 3D transmitter is engaged?[/quote]

This looks like a great find. I just tested this and see similar results. DPC was in the 4000 us range for me in WoW with 3D enabled. It actaully got as high as 8018 us. It does indeed look like the amount of flickering is directly related to DPC latency. Hopefully Nvidia can chime in on this. I did the same test with Left 4 Dead and with 3D enabled DPC latency was between 50 and 1000 us.
[quote name='enyar' post='508647' date='Feb 21 2009, 04:55 AM']Originally with an 8800 GTS everything worked perfectly for me. After installing a GTX 295 I had horrible flickering (several times per second.) After a lot of trying I was able to get to the point of no flickering. My machine is a Q6700 running at 2.66 GHz on a P35 with 8GB of 800 MHz memory. I'm running Vista 64.



I had ghosted my machine before I started reinstalling drivers and got everything happy. So I reverted back tonight to try and see what was different. As expected, my machine went back to flickering madly.



I noticed something with my delayed procedure call latency so I ran a test. With the a clean install of CD 1.04 drivers and playing WoW my DPC latency stays consistently below 1 ms. When I install the CD 1.05 beta drivers over top of this my DPC latency ranges from 3 to 4 ms. I overclocked my processor to 3.2 GHz and it may have been slightly lower but it was basically no change. I forced my USB to 1.1 with no change.



I then started WoW and toggled the 3D Vision on and off. While 3D Vision was on I was at about 3-4 ms and when 3D Vision was off my latency was about 250 us. A significant difference.



I then took my clean 1.04 install and installed the WHQL 182.06 drivers without updating the 3d vision drivers. The result was the same.



I assume the IR transmitter is a time critical device and latency has to be kept to a minimum for it to function properly.



I went through and disabled every piece of hardware I could (without blue screening) and it appears as though it is the graphics driver alone that is killing my performance. But only when WoW is full screen with the 3D turned on.



Does anyone else with flickering issues see the same result? Specifically do you see higher than normal DPC latency while the 3D transmitter is engaged?



This looks like a great find. I just tested this and see similar results. DPC was in the 4000 us range for me in WoW with 3D enabled. It actaully got as high as 8018 us. It does indeed look like the amount of flickering is directly related to DPC latency. Hopefully Nvidia can chime in on this. I did the same test with Left 4 Dead and with 3D enabled DPC latency was between 50 and 1000 us.

#2
Posted 02/21/2009 06:19 PM   
[quote name='logan0171' post='508826' date='Feb 21 2009, 01:19 PM']This looks like a great find. I just tested this and see similar results. DPC was in the 4000 us range for me in WoW with 3D enabled. It actaully got as high as 8018 us. It does indeed look like the amount of flickering is directly related to DPC latency. Hopefully Nvidia can chime in on this. I did the same test with Left 4 Dead and with 3D enabled DPC latency was between 50 and 1000 us.[/quote]

After doing that test, I was able to get rid of my latency by uninstalling all of the Nvidia drivers (3d, physx and graphics.) I then booted into safe mode and deleted everything that started with nv in the system32 and syswow64 folders. I rebooted then installed the CD 1.04 drivers (installed video driver, rebooted, installed 3d driver and set it up and immediately started WoW without rebooting.) I didn't change anything but the NVidia drivers and the latency went away and WoW is completely flicker free.
[quote name='logan0171' post='508826' date='Feb 21 2009, 01:19 PM']This looks like a great find. I just tested this and see similar results. DPC was in the 4000 us range for me in WoW with 3D enabled. It actaully got as high as 8018 us. It does indeed look like the amount of flickering is directly related to DPC latency. Hopefully Nvidia can chime in on this. I did the same test with Left 4 Dead and with 3D enabled DPC latency was between 50 and 1000 us.



After doing that test, I was able to get rid of my latency by uninstalling all of the Nvidia drivers (3d, physx and graphics.) I then booted into safe mode and deleted everything that started with nv in the system32 and syswow64 folders. I rebooted then installed the CD 1.04 drivers (installed video driver, rebooted, installed 3d driver and set it up and immediately started WoW without rebooting.) I didn't change anything but the NVidia drivers and the latency went away and WoW is completely flicker free.

#3
Posted 02/21/2009 08:43 PM   
[quote name='enyar' post='508883' date='Feb 21 2009, 04:43 PM']After doing that test, I was able to get rid of my latency by uninstalling all of the Nvidia drivers (3d, physx and graphics.) I then booted into safe mode and deleted everything that started with nv in the system32 and syswow64 folders. I rebooted then installed the CD 1.04 drivers (installed video driver, rebooted, installed 3d driver and set it up and immediately started WoW without rebooting.) I didn't change anything but the NVidia drivers and the latency went away and WoW is completely flicker free.[/quote]

I just tried to follow the same steps as you. I did not have a syswow64 folder on my system. In safe mode I ran a utility called driver sweeper. It removed a bnunch of Nvidia registry entries as well. After reinstalling the 1.04 cd I still have the same flickering problem in WoW. The good news is that it did correct another problem that I was having with Burnout.
[quote name='enyar' post='508883' date='Feb 21 2009, 04:43 PM']After doing that test, I was able to get rid of my latency by uninstalling all of the Nvidia drivers (3d, physx and graphics.) I then booted into safe mode and deleted everything that started with nv in the system32 and syswow64 folders. I rebooted then installed the CD 1.04 drivers (installed video driver, rebooted, installed 3d driver and set it up and immediately started WoW without rebooting.) I didn't change anything but the NVidia drivers and the latency went away and WoW is completely flicker free.



I just tried to follow the same steps as you. I did not have a syswow64 folder on my system. In safe mode I ran a utility called driver sweeper. It removed a bnunch of Nvidia registry entries as well. After reinstalling the 1.04 cd I still have the same flickering problem in WoW. The good news is that it did correct another problem that I was having with Burnout.

#4
Posted 02/22/2009 02:45 AM   
[quote name='logan0171' post='508982' date='Feb 21 2009, 07:45 PM']I just tried to follow the same steps as you. I did not have a syswow64 folder on my system. In safe mode I ran a utility called driver sweeper. It removed a bnunch of Nvidia registry entries as well. After reinstalling the 1.04 cd I still have the same flickering problem in WoW. The good news is that it did correct another problem that I was having with Burnout.[/quote]

Yeah it has nothing to do with latency. Mine is like 120 and my gtx8800 gets no flickering. If I use my gtx 280 I as do some others get flickering. I tried what the OP did. I read in another thread where what he did helped with the 295. But for me it did nothing. Flickering still strong.

man I really hope Nvidia is looking into this. I DONT like using my old 8800 when I have my 280.
[quote name='logan0171' post='508982' date='Feb 21 2009, 07:45 PM']I just tried to follow the same steps as you. I did not have a syswow64 folder on my system. In safe mode I ran a utility called driver sweeper. It removed a bnunch of Nvidia registry entries as well. After reinstalling the 1.04 cd I still have the same flickering problem in WoW. The good news is that it did correct another problem that I was having with Burnout.



Yeah it has nothing to do with latency. Mine is like 120 and my gtx8800 gets no flickering. If I use my gtx 280 I as do some others get flickering. I tried what the OP did. I read in another thread where what he did helped with the 295. But for me it did nothing. Flickering still strong.



man I really hope Nvidia is looking into this. I DONT like using my old 8800 when I have my 280.

#5
Posted 02/23/2009 05:22 PM   
Something else then the gtx280 must be contributing to your problem since my gtx280 has almost no flicker on anything i run. However it does flicker badly when I turn on SLI. I havent checked latency with or without SLI.. not sure where that is displayed...

[quote name='Zeeblade' post='509585' date='Feb 23 2009, 12:22 PM']Yeah it has nothing to do with latency. Mine is like 120 and my gtx8800 gets no flickering. If I use my gtx 280 I as do some others get flickering. I tried what the OP did. I read in another thread where what he did helped with the 295. But for me it did nothing. Flickering still strong.

man I really hope Nvidia is looking into this. I DONT like using my old 8800 when I have my 280.[/quote]
Something else then the gtx280 must be contributing to your problem since my gtx280 has almost no flicker on anything i run. However it does flicker badly when I turn on SLI. I havent checked latency with or without SLI.. not sure where that is displayed...



[quote name='Zeeblade' post='509585' date='Feb 23 2009, 12:22 PM']Yeah it has nothing to do with latency. Mine is like 120 and my gtx8800 gets no flickering. If I use my gtx 280 I as do some others get flickering. I tried what the OP did. I read in another thread where what he did helped with the 295. But for me it did nothing. Flickering still strong.



man I really hope Nvidia is looking into this. I DONT like using my old 8800 when I have my 280.

#6
Posted 02/23/2009 07:36 PM   
[quote name='Zeeblade' post='509585' date='Feb 23 2009, 01:22 PM']Yeah it has nothing to do with latency. Mine is like 120 and my gtx8800 gets no flickering. If I use my gtx 280 I as do some others get flickering. I tried what the OP did. I read in another thread where what he did helped with the 295. But for me it did nothing. Flickering still strong.

man I really hope Nvidia is looking into this. I DONT like using my old 8800 when I have my 280.[/quote]

DPC latency of 120us should not cause any problems. I start to see the flickering when it gets up over 2000-3000 or so. We are not talking about server latency in game. This is DPC latency which requires a piece of software to display. I keep the software up on my second monitor so I can see what is happening while WoW is running on my primary display. Check this site for more info on DPC latency [url="http://www.thesycon.de/deu/latency_check.shtml"]http://www.thesycon.de/deu/latency_check.shtml[/url].
[quote name='Zeeblade' post='509585' date='Feb 23 2009, 01:22 PM']Yeah it has nothing to do with latency. Mine is like 120 and my gtx8800 gets no flickering. If I use my gtx 280 I as do some others get flickering. I tried what the OP did. I read in another thread where what he did helped with the 295. But for me it did nothing. Flickering still strong.



man I really hope Nvidia is looking into this. I DONT like using my old 8800 when I have my 280.



DPC latency of 120us should not cause any problems. I start to see the flickering when it gets up over 2000-3000 or so. We are not talking about server latency in game. This is DPC latency which requires a piece of software to display. I keep the software up on my second monitor so I can see what is happening while WoW is running on my primary display. Check this site for more info on DPC latency http://www.thesycon.de/deu/latency_check.shtml.

#7
Posted 02/23/2009 11:21 PM   
Mine seemed to flicker any time my dpc latency broke ~1500 us. There may be more than one reason for the issue or we may not even have similar issues. I haven't seen yours and it might not even look the same though it sounds similar. Mine was flickering much more rapidly than what most others described too. I was getting about 1 to 10 flickers per 5 seconds. Things were not staying in synch well and I'd see the left eye staying dark and the right eye staying light.

I too had everything working flawlessly with an 8800 card only to have it fail miserably after upgrading.

To convince myself and to make sure it wasn't just luck, I played in some of the newer WoW zones with everything turned on and my fps dropped to and stayed about 12, but I still never saw it flicker unless I left the room with the glasses on. I did however get a little nauseous from the slide show sensation. Previously the flickering seemed to be worse in newer zones than old ones.

BTW, if your DPC latency is high and it isn't the Nvidia driver try looking for other device drivers that may be causing it. I.e. Ethernet adapters, wireless adapters, sound cards, etc. It may be an interaction between the 3d vision drivers and something else. If your DPC latency isn't greater than 1500 us or so though don't bother.
Mine seemed to flicker any time my dpc latency broke ~1500 us. There may be more than one reason for the issue or we may not even have similar issues. I haven't seen yours and it might not even look the same though it sounds similar. Mine was flickering much more rapidly than what most others described too. I was getting about 1 to 10 flickers per 5 seconds. Things were not staying in synch well and I'd see the left eye staying dark and the right eye staying light.



I too had everything working flawlessly with an 8800 card only to have it fail miserably after upgrading.



To convince myself and to make sure it wasn't just luck, I played in some of the newer WoW zones with everything turned on and my fps dropped to and stayed about 12, but I still never saw it flicker unless I left the room with the glasses on. I did however get a little nauseous from the slide show sensation. Previously the flickering seemed to be worse in newer zones than old ones.



BTW, if your DPC latency is high and it isn't the Nvidia driver try looking for other device drivers that may be causing it. I.e. Ethernet adapters, wireless adapters, sound cards, etc. It may be an interaction between the 3d vision drivers and something else. If your DPC latency isn't greater than 1500 us or so though don't bother.

#8
Posted 02/24/2009 01:02 AM   
Ok, I have measured latency with and without SLI for my GTX280's. Without SLI while running Warhammer Dawn of War it is less than 500us peaking at 1000 every now and then. With SLI on it jumps 30 to 50 percent higher averaging maybe 700 and slipping up to 1200us every now and then. With SLI flicker is every 5 to 10 seconds without SLI it is zero.

So SLI definitely jumps it up... seems strange..I would expect the opposite.. but it does not push it into the 1500 range.


[quote name='enyar' post='509733' date='Feb 23 2009, 08:02 PM']Mine seemed to flicker any time my dpc latency broke ~1500 us. There may be more than one reason for the issue or we may not even have similar issues. I haven't seen yours and it might not even look the same though it sounds similar. Mine was flickering much more rapidly than what most others described too. I was getting about 1 to 10 flickers per 5 seconds. Things were not staying in synch well and I'd see the left eye staying dark and the right eye staying light.

I too had everything working flawlessly with an 8800 card only to have it fail miserably after upgrading.

To convince myself and to make sure it wasn't just luck, I played in some of the newer WoW zones with everything turned on and my fps dropped to and stayed about 12, but I still never saw it flicker unless I left the room with the glasses on. I did however get a little nauseous from the slide show sensation. Previously the flickering seemed to be worse in newer zones than old ones.

BTW, if your DPC latency is high and it isn't the Nvidia driver try looking for other device drivers that may be causing it. I.e. Ethernet adapters, wireless adapters, sound cards, etc. It may be an interaction between the 3d vision drivers and something else. If your DPC latency isn't greater than 1500 us or so though don't bother.[/quote]
Ok, I have measured latency with and without SLI for my GTX280's. Without SLI while running Warhammer Dawn of War it is less than 500us peaking at 1000 every now and then. With SLI on it jumps 30 to 50 percent higher averaging maybe 700 and slipping up to 1200us every now and then. With SLI flicker is every 5 to 10 seconds without SLI it is zero.



So SLI definitely jumps it up... seems strange..I would expect the opposite.. but it does not push it into the 1500 range.





[quote name='enyar' post='509733' date='Feb 23 2009, 08:02 PM']Mine seemed to flicker any time my dpc latency broke ~1500 us. There may be more than one reason for the issue or we may not even have similar issues. I haven't seen yours and it might not even look the same though it sounds similar. Mine was flickering much more rapidly than what most others described too. I was getting about 1 to 10 flickers per 5 seconds. Things were not staying in synch well and I'd see the left eye staying dark and the right eye staying light.



I too had everything working flawlessly with an 8800 card only to have it fail miserably after upgrading.



To convince myself and to make sure it wasn't just luck, I played in some of the newer WoW zones with everything turned on and my fps dropped to and stayed about 12, but I still never saw it flicker unless I left the room with the glasses on. I did however get a little nauseous from the slide show sensation. Previously the flickering seemed to be worse in newer zones than old ones.



BTW, if your DPC latency is high and it isn't the Nvidia driver try looking for other device drivers that may be causing it. I.e. Ethernet adapters, wireless adapters, sound cards, etc. It may be an interaction between the 3d vision drivers and something else. If your DPC latency isn't greater than 1500 us or so though don't bother.

#9
Posted 02/24/2009 06:40 PM   
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