Freezing

[rocky289]

I have always been a windows user but thought I'd have a look at ubuntu.
First tried to install it on a older pentium 3 but didn't have enough horsepower to run the latest versions.
Did manage to get Lubuntu 12.04 alternate to run, but found it fairly limited.
So got hold of an AMD Sempron 3100 with 2 GB ram.
This was currently running XP Pro without any problems.
I tried Ubuntu 12.04, Linux Mint 13 & Lubuntu 12.04.
Same result with all.
System would freeze when I tryed to change anything.
Even in the demo mode.
Curser would dissapear & system would freeze.
Have to reboot.
Tried a veriety of solutions with no difference.
Different ram
Different Hard Drive
Different DVD drive
Different ribbon cables
Different mice, USB & PS/2

I had made DVD iso's & have since tried all on a 3rd system & they all go ok.
The problem system has onboard wired lan & also an addon wireles card.
Both were recognised during the testing.
No other addon cards or USB devices were present.
Anyone had this issue or have any advice on what might be causing the problem.