Hey there,

I exchanged my HD4890 to a new 6870 from Sappire. I used to have about 50 to 70 mhashes with the old one.
The strange thing with the new card is a sudden drop on system-load and performance. I have about 230 Mhashes/s, the card's fan is turning high.
Afer some time the performance drops down to 85 Mhashes/s and stays like that until it suddenly gets higher for a little while...

Since i used to use the poclbm-mod i was thinking that the mod might make a problem and used the normal poclbm-version instead.  --> same here

The drivers for the card are the newest, i also downloaded the latest stream sdk. 
I am part of bitcoinpool.com so i am participating and not just calculating on my own all the time if that is of matter. The system also is my workstation so i sometimes turn the application off.
What else can i do to go sure the gpu is not bored half the time ?