A few facts have been overlooked. There are two gerenerations of the iPod Video 5th Generation.
1. 30 & 60 GB models. First versions. These have the orginal motherboard 820-1763-A. The ones used in the 30GB 5G had 32MB RAM on them. The 60GB 5G had 64mb RAM on it.
2. Second version also know as Generation 5.5 also known as 5th Generation Late 2006. Motherboard 820-1975-A. The 30GB model had 32MB RAM on it and the 80GB model had 64MB on it.
So there are 4 different versions of the 5th Generation motherboards. To tell the difference between the 32mb and 64mb RAM versions you have to look at the memory chips on the motherboard or know for a fact whic iPod Apple shipped it with.
When loaded with the current release of the iPod software 1.3 the only differenence between the 5 and 5.5 boards is the that the 5.5 boards will have SEARCH and the original motherboards will NOT have SEARCH function.
All 30GB motherboards have 32mb RAM on them.
All 60 & 80 GB motherboards have 64mb RAM on them.
A 32MB motherboard will recognize a 240 GB hard drive under Software 1.3 but will run out of memory at around 7,500 songs. After that you can't load any more songs even though there will plenty of hard drive space left over. So anything beyound about 120GB is wasted with a 30GB 32MB motherboard Gen 5.0 or 5.5.
A 64mb motherboard can handle around 20,000 songs. I have 16,476 on my 240 GB drive and I still have 103 GB free. I have TWO iPods with the 240 GB drive in them. One is an upgraded 60GB iPOd with motherboard 820-1763-A with 64mb RAM. The other is an 80GB iPod with the 820-1975-A 64mb motherboard. Both work well with Software 1.3 but with lots of songs SEARCH is worth having.
The best hard drive for a 30GB iPod 5 or 5.5 gen is the Samsung SpinPoint N3A HS12YHA 120GB. It will fit in the 30GB case with no mods as it it 5mm thick.
The best hard drive for a 60 or 80 GB 5 or 5.5 iPod is the Tosiba 240GB MK2431GAH hard drive. It fits the thicker case with no mods as it is 8mm thick. I bought mine off of eBay.