I use cgminer-2.3.6 on my HD 5870 and received 460-462 Mh/s.
In the new version cgminer-2.4.0 was just 418 Mh/s.
Sys. Win7x64 + OpenCl from AMD Catalyst 12.5 Beta
http://www.ngohq.com/home.php?page=Files&go=giveme&dwn_id=1624Maybe, you should pay attention to the new drivers and optimize a new version of CGMINER
Wrong, you should downgrade your driver and read the FAQ.
If you mean that question,
Q: The CPU usage is high.
A: The ATI drivers after 11.6 have a bug that makes them consume 100% of one
CPU core unnecessarily so downgrade to 11.6. Binding cgminer to one CPU core on
windows can minimise it to 100% (instead of more than one core). Driver version
11.11 on linux and 11.12 on windows appear to have fixed this issue. Note that
later drivers may have an apparent return of high CPU usage. Try
'export GPU_USE_SYNC_OBJECTS=1' on Linux before starting cgminer.
I know about it.
The problem is:
cgminer-
2.3.6 + OpenCl from AMD Catalyst
12.5 Beta =
462Mh/s
cgminer-
2.4.0 + OpenCl from AMD Catalyst
12.5 Beta =
418Mh/s