FTB - 1.6.4

[Rushman0]

I've installed Direwolf20's new 1.6.4 modpack.
It's loads of fun except for the constant irritation being random freezes.
Roughly 15-20 minutes after beginning playing I being random screen freezes and the longer I stay on the more frequent they become until I can't play at all, thus force closing minecraft.

Any ideas how I can solve this? I'm currently allocating 6gb of RAM out of 12.

 

[Ashzification]

Please complete this:
http://desk.feed-the-beast.com/index.php?/Knowledgebase/Article/View/9/0/basic-troubleshooting

If you're still having trouble, please post your complete client-side (launcher) console log to pastebin.com and link your paste URL here.
The console log is the one described under the first paragraph in this article. Please post your logs as described to prevent them from expiring.
http://desk.feed-the-beast.com/inde...29/1/what-log-do-you-need-where-can-i-find-it
Then post in this format:

Operating System, bit type:
Java version/update, bit type:
Launcher version:
Completed the troubleshooting guide (y/n):
Console log, pastebin.com link:
Description of the Issue:

If your console log indicates that you have not completed the guide exactly as I have prepared it, then I will ask you to do it again.