Because Premiere Elements does not edit GoPro natively, you'll need to render the video continually as you work -- whenever you see yellow lines above the clips on the timeline in Expert view. To render, press the Return/Enter key or click on the Render button.

You're working with the trial version of Premiere Elements, so it hasnt got all of the components installed. You'll get a bit better performance when you buy and register the program -- but, with GoPro footage, there are not guarantees. The program can edit it somewhat. But, with a laptop that's giving your marginal performance, it may not be the best software for you.

Try rendering the timeline and see if that improves your performance to an acceptable level. If it still seems sluggish, I'd recommend you not go with Premiere Elements and consider another editing program.

If you are editing AVCHD, or any other H.264 material, the CPU will be the most important factor for smooth editing and playback. I recommend a fast i7, but some do get by with a slower i5. It boils down to their tolerance for slow and choppy playback.

Now, the GoPro 3 can shoot in several formats, and if I understand correctly (do not have one), it can record up to 4K, which is a professional format, often used by Hollywood. If one is planning to edit 4K, then they do not want a laptop, but a full editing workstation, built expressly for editing that material. However, if one is shooting AVCHD, then the computer specs. fall dramatically. Then, a fast CPU, as much RAM as is possible, and ideally a 2x HDD (or SSD/HDD) I/O setup will be just fine. One will not need dedicated RAID arrays for the media and Export drives. Go to 4K footage, and the requirements go up exponentially. This is because of the high number of pixels in 4K footage.

As I do not do Mac, and do not know their equipment, I can only talk in very general terms. Our MOD, Steve Grisetti, does use a Mac, and edits AVCHD, so he can offer more specific Mac recs.

Good luck,

Hunt

The yellow lines you are refering to are the horizontal ones going across the clip about 3/4 to the top?

That sounds like the Effects Keyframing "rubber band." The colored lines referred to are the ones above the Clip right below the Timeline Ruler. This article goes into more detail, though some of it is for PrPro: http://forums.adobe.com/message/4068277#4068277

Good luck,

Hunt

If you have no colored lines above your Clips, when they have been dragged to the Timeline, that means that your Clips match your Project Preset 100%.

Good luck,

Hunt

With the Duo-Core CPU and limited RAM, when working with H.264 material, I would say that is about right, but do not have a computer with similar specs. to benchmark for you. Maybe others, with similar machines and footage, can comment.

Good luck,

Hunt

The single 5400rpm hdd isn't helping.

You are correct there. To effectively edit video, one really needs a 7200 RPM min. HDD, and spreading the I/O load over two, physical 7200 RPM HDD's, will benefit greatly.

Good luck,

Hunt