china white:
If you want to go back intraday on Qcharts, you can go back years. I've been back to February 1999 intraday.
However, as this pulls significant amounts of data off their servers, I find that the best time to do this is at weekends, ie when the servers are not being used by many. This makes it much quicker, and it only takes a minute or so to be back three years.
I can't remember the last time that Qcharts froze - and if it ever does happen you just change servers. Press Ctrl Alt N and then pick a server based on ping times.