I know it's an old post but it came up in a search so I'm updating for those still using M68MT rev3 boards:
Correction, it does allow a few more XMP timings but support is spotty apparently.
At XMP 533, which allows lower CL etc., the HT can still be set but the NB has to be left on auto (have to use higher NB voltage and makes more heat)
XMP 711 mhz works and allows HT and NB multipliers to be set.
Running a faster NB helps with on chip cache access and will get faster times for superpi and the like but it kills memory, hardware access and generates a lot of heat, best to set it at 3x memory ( actual frequency, not bandwidth freq) to run games, applications and allows better HW communication.
Current stable and cool settings for 1045T@3.6GHZ are:
FSB : 267
HT multi: 3 resulting in 800MHZ (4 would be ideal @ 1066 but it won't allow because it's over 1000, yet auto will set it sky high)
NB multi: 8 - which yields 2133MHZ
mem multiplier: 5.33 for 1423MHZ (XMP 711)
timings - per memory XMP711 profile
memvolt - 1.65 - required for my mem to use XMP
Corev - +0.05 (+.025 @250FSB)- not actual increase, allows it to post so cool n quiet takes over and pumps it to 1.375 - 1.425 based on use, not required for this processor @240fsb and less.
NBvid: Auto or .075, manual setting may be required if you run very high NB (like when the BIOS doesn't allow)
same settings for mem @ 1066 except the 4x mem multiplier.
FSB250 - mem 5.33x for 1333, 4x ht, 8x nb. Won't start all the time at CPUv +0 but it allows C&Q to idle cores and possibly core boost to work. With nb and ht set like this it'll run on a stock cooler without running really heavy apps.
FSB240 - mem 6.66x for 1600(XMP), 4x ht, auto nb and nbv. C&Q runs, idles cores, maybe coreboost works, stock cooler. Can set CPUv to -.05 if C&Q is not wanted to stay in stock cooler range.