My 8400 did 4400 (489x9) memory at 978 with the following settings

Cpuv: 1.3500
Cpu term: 1.200
PLL 1.50
CPU ref 0.760
MCH 1.340
MCH ref 0.740
MCH DDR 0.910
ICHIO 1.50
ICH 1.10

This was prime stable small fft for over 10 hours. Max temp with TRUE120 was 57c.