It's not critical, but you'll get far better performance if you have.
This is my pet checklist for questions regarding FCP X performance - you may have already addressed some of the items but it's worth checking.
Check the spec of your Mac against the system requirements:
Check the spec of your graphics card. If it's listed here, it's not suitable:
Make sure you're using the latest version of the application - FCP X 10.0.3 runs very well on my 2009 MacPro 2 x 2.26 GHz Quad-Core Intel Xeon with 16 GB RAM and ATI Radeon HD 5870 1024 MB. I run it with Lion 10.7.3.
Check that you have at least 20% free space on your system drive.
If you have not already done so, move your Projects and Events to a fast (Firewire 800 or faster) external HD. Make sure the drive's formatted OS Extended (journalling's not required for video). You should always keep at least 20% free space on the Hard Drives that your Media, Projects and Events are on.
If you are getting crashes, there is some conflict on the OS. Create a new (admin) user account on your system. Do NOT import any of the settings etc from the old account - simply use FCP X from there - if it runs a lot better, there's a conflict and a clean install would be recommended - but remember, if you reinstall the system, and then use Migration Assistant (or anything else) to import all your old settings etc etc, you may well be importing the cause of the conflict in the first place.
Keep projects to 20 mins or less (about half that for Multicam). If you have a long project, work on short sections, make them into Compound Clips and then paste these into a final project for export.
If you ever experience dropped frames, I strongly recommend you use ProRes 422 Proxy - it edits and plays back like silk because the files are small but lightly compressed (not much packing and unpacking to do) - but remember to select 'Original or Optimised Media' (FCP X Preferences > Playback) just before you export your movie, otherwise it will be exported at low resolution.
If you have plenty of processor power, for the ultimate editing experience, create Optimised Media - most camera native files are highly compressed and need a great deal of processor power to play back - particularly if you add titles, filters or effects. ProRes 422 takes up much more hard drive space but is very lightly compressed. It edits and plays back superbly.
Hide Audio Waveforms at all times when you don't need them (both in Browser and Storyline / Timeline). They take up a lot of processor power. (Use the switch icon at the bottom-right of your timeline to select a format without waveforms if you don't need them at the moment, then switch back when you do).
Create folders in the Project and Events libraries and put any projects you are not working on currently, in those folders. This will help a lot. There's a great application for this, called Event Manager X - for the tiny cost it's an invaluable application.
Unless you cannot edit and playback without it, turn off Background Rendering in Preferences (under Playback) - this will help general performance and you can always render when you need to by selecting the clip (or clips) and pressing Ctrl+R.
The biggest single improvement I saw in performance was when I upgraded the RAM from 8 GB to 16.
I have been searching for a while on this simple question (What are best external HD attributes for FCPX?). This thread leads me to believe you guys have the answer.
My MAC is early 2011. 2GHz Intel Core i7 8 GB RAM. I am not trying to do anything fancy with FCPX. Just home movies of the kids. I have about 400GB now (and growing) on my internal HD and I use iMovie. I have not started using FCPX yet.
I am looking for your recommended attributes (not necessarily the "minimum" attributes) of a hard drive to use with FCPX.
Here are my specific questions (easiest to hardest)
Formatted OS Extended (journaled or not - either is ok. Right?)
Interface: Firewire 800 or faster was stated above.
What about a GigE NAS connected directly to Mac? Would performance be acceptable?
Is Thunderbolt over kill (I know the price is.)?
RAID 0: Would a RAID 0 system be worthwhile for performance or would a regular 7200RPM HD work fine?
RAID 1: I like RAID 1 for redundancy but will there be a performance concern? I guess if I use FW800 or better, the performance would not be an issue? Or would I need Thunderbolt for the performance not to be an issue with RAID 1?
Recommended devices? I heard G-Tech is good. WD has one of the cheapest Thunderbolt drives that can do RAID 0 or RAID 1 (WD My Book Thunderbolt Duo)
Thanks in advance