Hi, the issue here depends more on the type of source video you have than your GPU specs. As other have mentionned. I'm guessing you are using h264 videos as source. This is the most common file format for HD content, but the issue when editing it, is that it's not frame based, but GOP based. What that means, is that, in order to compress the video, the codec won't encode every frame, but only 2 or 3 over one second of video. The in between frames are reconstructed by using complicated math that basicaly store moving pixel data. The thing is, that decompressing these frames takes a lot of ressources. That's probably why your timeline is yellow and not green. Premiere have less difficulties to just plainly read frame base codecs (such as QT animation, or image sequences) than recontructing GOPs in GOP based codecs (GOP stands for Group of Pictures). Knowing that, when you speed up your footage, Premiere will have to actually decode more GOPs in a shorter period of time, and that's where you will see your realtime playback drop frantically. Premiere uses a lot of ram to store the decoded frames, and if you run out of ram, Premiere will have to trash the decoded frames and store the new ones. You can see how this can be a bottleneck quite fast. What I would recommand to try, if storage space on your HDD isn't an issue, is to transcode the original clip you want to speed up into an image sequence or in a quicktime animation format. Then bring it into Premiere, speed it up, and see if your preview behaves better or not. But as Jim said above, the most important is that once exported, your sped up footage works as intended. Hope this helps, Seb
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