Hi Neil,
There should be no problem opening CS4 projects in CS6. That said, it is good practice to try and wrap things up before the update “just in case”, but you ought to be safe. I’ve not had any issues in this area myself.
Regarding system hardware, if your PC is 3, 4, 5 years old, you may want to seriously consider new hardware. Note that CS6 requires a 64-bit OS, so you’d need to upgrade to Windows 7 Pro 64-bit for instance. Does your hardware support a 64-bit OS? Are there 64-bit drivers available for the motherboard?
Your RAM is inadequate, even for current config should have been maxed at 4GB with Win XP for better performance. 8GB is a good minimum for CS6, but 16GB is even better (RAM is cheap today).
Premiere CS6 can benefit from Nvidia graphics card technology to offer hardware acceleration in CS6. Most likely you would need a newer display card to take advantage of the “Mercury Playback GPU Acceleration” features.
Do you edit HD, or intend to move in that direction? AVCHD and DSLR codecs will bring older hardware to its knees in a hurry, meaning it may not even play back without stuttering badly.
An Intel Core i7 processor and Nvidia graphics are the basis of a decent CS6 editing experience these days. With SD video for instance, imagine exporting a 2-hour production to MPEG-2 for DVD in 10 minutes. Seriously. Or exporting HD to Blu-ray or YouTube in close to realtime or better.
You could add Windows 7, more RAM, updated display card, etc. to your system, but it will still be very slow compared to even an entry-level Core i7 system. These have 4 cores running 8 threads, and the entire system architecture is just faster in every way, so it’s more than just the processor. Faster RAM, faster hard drive interface (SATA 6Gb/s), faster data transfer all working together.
If you are still cutting DV footage only, then you might get away with updating current system and it could work out for you, but not so much for HD.
Thanks
Jeff Pulera
Safe Harbor Computers