Are you planning on going SLI? If yes, then I recommend the Asus P5W DH Deluxe and modded drivers. It is a much better overclocker (the board you mentioned was also one I considered until I found out it still uses old Nforce revision chipsets and is considered a very limited overclocker). As mentioned above all Conroe's are upwards locked except the X6800. Apparently though, there is a possibility of unlocked multi's with the Asus P5B (Although bear in mind that the two PCI-E slots are 16x/4x, not 16x16x like the board you mentioned or 8x8x like the Asus P5W DH Deluxe (975x chipset)
"The new 0507 BIOS for the P5B Deluxe, dated 8/10/2007, has two new and exciting features:
Provide better maximum overclocking.
Add the ability to adjust the multiplier of most Conroe CPUs even if they are not Extreme Edition.
Even more exciting is that ASUS says they have found a way to unlock up or down most Conroe chips. This will be a significant new feature that is highly desired by many Core 2 Duo buyers. It didn't take but a few minutes for us to get the new BIOS flashed and a Core 2 Duo chip mounted to check this out."
"First, we should note that certain Gigabyte P965 boards also allow downward unlocks with the latest BIOS releases. ASUS joins them in offering this feature, and they have broken new ground with the 0507 BIOS for the P5B Deluxe. The ability to specify multipliers - even if it's only downward unlocked - is so significant that every other manufacturer will have to follow suit or lose market share to the two motherboard giants.
At present, every Core 2 Duo chip we tried unlocked down (this included both B1 and B2 steppings); however, none of our samples unlocked both up and down. ASUS tells us that many Core 2 Duo chips also unlock upwards, but the upper limit is around a 14X multiplier with those chips that do unlock in both directions. If true, we're certain those chips that can unlock completely will be quickly figured out by enthusiasts and those models and steppings will become the most highly desired Core 2 Duo chips."
Very nice, unlocked multi on lower end conroe.
Whether or not this becomes available for the P5W DH Deluxe is debatable but likely.