Though I would just compare the both of these for people.
Took delivery of the V3 yesterday as a build for my little brother to take back to uni with him.
The build and setting up of the new arrival was infact identical to the V2 and was ready to switch on in no time at all.
Switch on came and the first thing that I gladly notice was the new settings in the BIOS. The first being the new fan settings choice, gone is the different temp scales, now it's replaced with a ultra low, low, medium and high settings for the fan ( 750rpm, 1500, 2500, 3500 ). Also then it has a thresh hold setting of either 40oC, 45, 50, 60. I take it it must hit the next level of fan when the temp of choice has been hit. This BIOS choice beats my V2 running a Panaflow 23db to try and get noise level down any day, and I believe the V3 is in fact a 92mm ICE not the 80mm that the V2 comes with, but no details can be found and at this time I have no access to the V3 to check ( its already gone to a LAN! )
Second and a rather funny one, but I’m sure someone somewhere will be thanking the guys at shuttle, and that the choice of the brightness of the blue system led light. It can be changed any were from off to 100% in steps.
I haven’t had much chance to look up much else in the BIOS but I’m not aware of anything else major that has changed.
Now comes the seriously worrying part.
When I'd installed Windows XP I now needed to install the NVIDIA software, and if you don’t have the CD that came with the Shuttle your out of luck! Shuttle and NVIDIA have zero support or even existence of this V3 on their sites, and I tested the V2 CD and that is incompatible. So keep that CD safe!
Still a bit worried why the V3 has nothing mentioned on the Shuttle site and the V2 is specd as the latest.
Something that arises on both the V2 and V3 is the constant problem of crashing in windows right until the time you can get a Radeon Driver installed, this happened on two different Radeon 9800pros too in two different Shuttles!
After everything was installed and running I had time to do some CS:S stress tests to get the heat up, along with Prime95.
It seems that in CS:S I was having random freezing, after running Memtest it seemed there were memory errors galore. Taking a 512mb out and running a single 512mb ( pc2700 for the time being ) worked, and the other stick worked alone. After putting the second stick in again the Memtest worked faultlessly and CS:S had no problems. So it's always worth swapping RAMs around and testing single sticks! Some OCZ PC3200 has now been ordered.
Temp wise the little bro somehow managed to give me a heart-attack when I was seeing 58oC idle, but lucky I noticed how quite the fans were by now, and the fan had been reverted to 750rpm ( ultra low in the BIOS ). This makes the fan nearly inaudioble. Low is the best setting for myself as its only a quite hum and at twice the ultra low speed probably the better setting all round for your shuttle. Medium gets a little louder and probably a little loud for most Shuttle owners, high is full 3500rpm and only a serious hammering at maybe a LAN would ever constitute this being set.
Hope that’s of some use to someone, and all in all the V3 is well worth purchasing over the V2 but obviously not even worth considering a upgrade from the V2 to V3