Freazing when i put mouse poineter over thread title :)

[sybrows]

Hiya .... Firstly this is not a new thing for me (not since the change) more enquiring if anyone else gets a sys freeze for 20 secs when your mouse goes over a thread or post title. It may be user specific but thought it was worth a mention. Its not every time, just more like the first time i do it, it seems to try and cache (or at least pages to the hdd a lot.) I am doing a format soon so will see if this aids the situ. But really just to let you know.
Stats are :

Browser: Firefox 1.0.4 (but been happening since 0.9x)
OS win2k pro sp2 all updates (again as above)
HDD: IDE NTFS

Have a few apps in the background but nothing that really stands out as makin it happen.
BTW I have nil knowledge of vBuletin so if this is a known prob then please ignore and tell me to send a HJT Log
yours BrOwey