et un nuxnuxien de plus 
pour le mot de pass
tu lance le teminal
sudo passwd et tu suis les instructions.
perso, xubuntu et lubuntu, bof bof, trop lite à mon gout
ubuntu pas de soucis
debian en mode server
pour savoir la ram installée
dans un terminal
cat /proc/meminfo
ca donne un truc comme ca
MemTotal: 4046008 kB
MemFree: 157700 kB
MemAvailable: 1814384 kB
Buffers: 345652 kB
Cached: 1470884 kB
SwapCached: 464 kB
Active: 2301912 kB
Inactive: 1179172 kB
Active(anon): 1410600 kB
Inactive(anon): 368104 kB
Active(file): 891312 kB
Inactive(file): 811068 kB
Unevictable: 0 kB
Mlocked: 0 kB
SwapTotal: 4110332 kB
SwapFree: 4108700 kB
Dirty: 464 kB
Writeback: 0 kB
AnonPages: 1664092 kB
Mapped: 546216 kB
Shmem: 114152 kB
Slab: 281580 kB
SReclaimable: 242720 kB
SUnreclaim: 38860 kB
KernelStack: 11024 kB
PageTables: 39740 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 6133336 kB
Committed_AS: 6777796 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 0 kB
VmallocChunk: 0 kB
HardwareCorrupted: 0 kB
AnonHugePages: 577536 kB
CmaTotal: 0 kB
CmaFree: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 269888 kB
DirectMap2M: 3923968 kB
DirectMap1G: 0 kB
pour le processeur
cat /proc/cpuinfo