your specs seem high enough, so I guess it a coding bug but you say it haapen frequently thats what I find strange since ive not seen this thing reported before, I assume your not using the Vista beta releases. Perplexing situation you got there.....MeltingIce (orginal creator of Sky Explosion) might know what happening. Jo,Matt, or JavaJones might also find this intrestnig (they are Planetside staff). Im sorry I haven't been able to give you anything diffenitive sashley but other may know more about this then I do.
Regards,
Will