Adding GPU Accelerated Cuda Effects is suddenly very laggy?

Question

Hello Adobe Experts,
I am appealing for some help with an issue that has bugged me for a little while. The best way to explain it is to show you the problem in a short 4 minute video which I will post below for those who have the time to take a look. Failing that my description is beneath the video.
Essentially, I upgraded to Premiere Pro CS6 from CS5.5 and discovered GPU acceleration. Wow! I subsequently was due to upgrade my iMac and bring in the specs to make the most of this technology, especially within colour correcting and grading. The new machine we got is a 2012 Mac Pro 12 core (2 x 6 cores 2.4Ghz) with 32 GB Ram and a Nvidia Quadro 4000 for Mac (2GB). It also has an SSD drive as the OS boot and applications drive so hoping that things would be super quick.
For a time they were, I can remember adding the Fast Color Corrector effect to a video clip and dragging the wheel around and everything would move in realtime, the program monitor was updating as I moved the mouse within the colur wheel. It was smooth and silky which I just loved as it meant that colour correction/grading would be now very easy to accurately dial in a look quickly and then move to the next clip. Plus no need to render afterwards either, hooray!
Then recently, and I am not sure what has caused this, it stopped working as well?!? I still don't have to render the clip after adding the effect or making a change to the parameters, however the process of making the change has become slow, unresponsive, laggy, delayed, laboured or any other similar adjectives. Now when I drag the mouse in the colour wheel the update happens in delayed steps and it is certainly anything from smooth and silky anymore. The problem with this is that it is very hard to accurately and quickly move the parameters around and make those fine adjustments which in turn slows down the process greatly.
I am really keen to know the following:
Does anyone else with a similar system have these issues?
Is this just how it is? (Trouble is I remember it being much faster and more responsive. Also I watched Maxim Jago at a workshop and he didn't seem to struggle with these issues when showing off GPU acceleration and adjusting effect parameters, even during playback)
Is it a hardware issue? Does my GPU need to be faster or is it not being correctly allocated to Premiere Pro?
Is it a software issue? Is it something that has come about in more recent versions of Premiere Pro?
How can I go about resolving this issue?
So far I have tried a fair few things like resetting preferences, ensuring the GPU acceleration in the 'Memory' preferences tab is turned on, clearing media caches, removing and reinstalling Premiere Pro et cetera.
If any experts from the community can help or indeed anyone from Adobe can help me resolve this issue, or at least feed back thoughts and comments, then I would be so grateful.
Best wishes,
Alex

Answer 1

Hi Maxim and JFPhoton,
I'll try and come back to all those points:
To JFPhoton-
which version of PPro are you using......CCloud, or CS 6 ? - CC Latest version
is your RAID setup configured in RAID 0......what were test results for speed ? Three internal HDD 3TBs striped together for maximum throughput. Speed results =
To Maxim Jago-
Yes I have reset the preferences. I have also unisntalled Premiere and then reinstalled it. Also completely reinstalled my OS just in case.
Playback is running at full res and has been since I got the machine - never had an issue from the start and then all of a sudden..... meh!
I have three internal HDDs (3TB) striped together in raid for maximum throughput which are pretty quick (speedtest above). I did try to check this though by putting source content onto my boot drive which is an SSD and then trying to see if issue exists in this case which it does. I also tried transcoding to other codecs than h.264 and the problem is still present.
Yes there is a fair bit of software running in menu bar. Used to have iStats running which I have removed now and problem still persists. Others I wouldn't think should be taxking the GPU. Although I will try quitting out of everything none essential.
Definitely up to date on most recent version of PPro
The Quadro 4000 was superb once I first got it. As mentioned above, I could perorm all the edits to the mentioned effects with ease at full res whilst plyaing back and everything working fine! I just wonder however if the card may have developed a fault or need cleaning out of dust or something? (quite a lot of dust present when I last opened the side door). Is there a way to check this?
Same problem persists across different projects and codecs.
As I just mentioned to Maxim, I wonder if my GPU has developed a fault? The reason I say this is because sometimes my monitor doesn't come on correctly (just shows a black screen) and I have to turn on and off again. Also, sometimes within Premiere I have an issue where I resize a window and I get 'ghosting' of that window as I drag. Did also previously have an issue changing between colour correction workspace and editing workspace. The workspace simply wouldn;t change and everything was completely unresponsive. I just wondered if anyone knew a way to check the GPU without taking it out of the machine or indeed if this might be the cause of my problems?
Thank you so much for taking the time to respond. I really really appreciate it.
Best wishes