FINALLY! Barcelona(s) + Asus L1N64......

[tictac]

North Bridge multiplier
Target register is F3x0D4.
We can observe the value like C331F024 on F3x0D4 with MchbarEdit,
and last digit (4 in the above case) is NbFid, i.e. NorthBridge Frequency ID.
NB clock is defined as "200 x (NbFid + 4) / (2^NbDid)"
NbDid, i.e. NorthBridge Divisor ID is defined at MSRC001_00[68:64], and it's 0 in default.
2^0=1, so we can think simply NB clock = 200 x (NbFid + 4).
We need to reboot to give effect to changing F3x0D4[NbFid].
# Oppositely, NbDid is changeable without reboot, so the system can reduce NB clock dynamically.

Additional information to access it with WPCEDIT

With 2 processor there are 2 register need to be edit :-

1) Processor node 0 = Bus#0 Device#24 Function#3 (For processor number 1)
Offset D4h (32bit access mode) , Bit 0,1,2,3,4 (5bit)

2) Processor node 1 = Bus#0 Device#25 Function#3 (For processor number 2)
Offset D4h (32bit access mode) , Bit 0,1,2,3,4 (5bit)

NB clock = 200 x (NbFid + 4).
*NBFid = in decimal


Bit = Hex = Decimal = NB Speed calculation
00001b = 1h = 1 = NB clock 200x (1+4) = 1000MHz
00010b = 2h = 2 = NB clock 200x (2+4) = 1200MHz
00011b = 3h = 3 = NB clock 200x (3+4) = 1400MHz
00100b = 4h = 4 = NB clock 200x (4+4) = 1600MHz
00101b = 5h = 5 = NB clock 200x (5+4) = 1800MHz
00111b = 6h = 6 = NB clock 200x (6+4) = 2000MHz
....
11011 = 1Bh = 27 = NB clock 200x (27+4) = 6200MHz