We have a old computer used to install QNX, another guy installed 6.3.2 first. Then I installed 6.4 on that. When I was 
installing 6.4, it said BIOS does not support 20G harddisk, only suppert 8.4G, give me two option to choose: 1) install 
under 8.4G, 2) let QNX handle all disk.  I asked the other guy, which option he choosed when installing 6.3.2. he said 
he forgot. So I choosed let QNX handle all harddisk and assigned 5G ppartition to 6.4. After installation, 6.4 can run 
normally, but 6.3.2 said it cannot find some library file. I used Fdisk to check partition, found 6.3.2 used a 8.4g 
partition, and 6.4 is 5G partition. I updated BIOS to latest version, and  in BIOS it says harddisk is 20G. Currently, 
if I use FDISK to set one partition to be active, the QNX on that partition works fine, and other one cannot work. Can 
both QNX work without using FDISK to set active partition? another question is why qnx has type 78,79 partition, what's 
the difference/ thanks