^^ I fully endorse what gx_saurav has stated.
Give a go-bye to any old cabinets.Though a bit costly The Zebronics CUBE case is a better choice and you do need a good SMPS with atleast 380W and above and a reputed one at that.Do not skimp on it and go for no-name brands.
There are already reports that the Northbridge in the Gigabyte MB runs very hot and people are worried, though no catastrophic failures have been reported under normal usage conditions ( no overclocking ).
Given that so much is packed in so little a chip, that is understandable and good case ventilation is very important.
In the Zebroncs CUBE case, the bottom fan of the SMPS blows air directly on to the Northbridge in the lower compartment (see the pictures elsewhere on this thread). Therefore this case is ideally suited rather than a tower case.
So choose an SMPS with a fan at the bottom.I was not aware of this but luckily, the VIP Gold 400W, I chose, has a bottom fan and so I am happy that I made a correct choice of the case and cabinet.I would have erred had I chosen an SMPS with the usual fan at the back only.
I have now been running the HTPC for almost 20 hours a day for the last twenty one days.( I still have 9 more days to activate Vista
) The AMD overdrive program ( which I use only for monitoring) reports tmpIN1=42 C, tmpIN2 =44 C and TmpIN3=87 C. The last one is presumed to be that of the Northbridge.(82 to 90 is what is being reported by other users).( I did not check the temperatures immediately after installing the AMD overdrive, when I had kept the case fully open)
As already reported a clean install of Vista Home premium SP1 requires 15GB for OS alone.
The current breed of motherboards support XP and Vista only since most software vendors have stopped providing drivers for Win9X/Win ME. So don't even think of them.
Note: Though AMD Overdrive is slated to work on this RS 786 motherboard with the latest F3 bios update, there still appears to be some bugs, which AMD/ATI/the bios manufacturer have to sort.For example the CPU core temperatures are read as 0(?).I have tried to ascertain as to what are tempIn1,tempIn2,tempIn3 but no info.The user manual just states value of temp sensor1, 2 and 3.So tempIN3 represents the northbridge temperature is at best only a guess by many.If there is any clarity on this I shall post the same.For now take it with a pinch of salt as I do.