Unless you live in a hot environment and your case has poor ventilation it isn't your NB heat holding you back at 380FSB. I'm at 426FSB with nothing tacked onto my NB.
That said, here's the bios settings I used (that require changing) for 400FSB.
Advanced Bios:
- Limit CPUID = Disabled
- C1E = Disabled
- TM2 = Disabled
- EIST = Disabled
- Virtualization = Disabled
PNP/PCI:
- PCI Latency = 32
M.I.T.:
- CPU Clock Rate = 8 (depends on your processor, 7 for 6300, 8 or 6400, 9 for 6600, etc)
- CPU Host Clock Control = Enabled
- CPU Host Frequency = 400 (Whatever FSB you want to run at)
- PCIe Frequency = 100
- CIA2 = Disabled
- System Memory Multiplier = 2.00
- DRAM Timing Select = Manual
- Timings = 4/4/4/12 (depends on your RAM)
- System Voltage Control = Manual
- DDR2 Overvoltage = +0.3 (depends on your RAM/timings)
- PCIe Overvoltage = Normal (default)
- FSB Overvoltage = +0.1
- MCH Overvoltage = +0.1
- CPU Voltage = 1.35000v
Using the same settings at 426 aside from CPU Voltage at 1.37500 and DDR2 Overvoltage at +0.4. Also of potential note I have 80mm fans in my case at: 1x side intake in vid card area, 2x rear exhaust, 1x exhaust at the top of the case. At 426 I idle at upper 30s and Orthos blend at low 50s. Also I disabled Smartfan and it dropped my CPU temps by a large amount and didn't make my case any louder. Though others might differ if they have quiet 120mm case fans, I didn't hear a thing over my 80s.