very slow file copy disk to disk

-- vista32bit ultimate.2x750gb sata hdd. 4gb ddr3 ram.intelquad core q9550
2.83ghz cpu 1330fsb asus mobo ..and OC...I have asked a similar question to
this but had no real replies : when copying and pasting or even cut and paste
large files i.e 3 to 10gb
either between disks or from a dvd to disk the speed of the transfer slows
dramatically i.e from 50MB/s to 5mb/s...the processor is running say at
4-17%..memory is at say 12-26% I have tried larger or smaller pagefile and
included ready boost via a usb flash drive ...to no avail I cannot track down
the reason for this....any help appreciated and any one who has had or is
having the same problem please let me know:....
for those who remember its akin to downloading with a dial up connection
...it starts off rapidly and slows very fast >
jph

[Pasow]

I’m having the same problem but it caps off normally at 10MB/s for me.. after a first half a minute of 50MB/s...