Help!!

Wrote recently as PC becoming unstable and seemed to coincide with installation of Fuji digital camera software. Eventually a system 32 error came up and we repaired from XP disk. Then all running ok ish for about 3 weeks. Then started to go wrong again. Began to freeze or crash during use - often during games - and couldnt restart in any way and had to switch off. Also began telling us on booting: "Warning - frequency has changed". Now can't start computer - it just beeps about 5 quick beeps and Mitsubishi monitor goes into power save straight away. Can't access safe mode or activate monitor menu system. Tried using a different monitor to see what was happening, but went to power save too. We have no idea what the problem(s) is (are) or even how to go about things or even in which order.

Someone did reply previously to this suggesting that it was the RAM if the PC beeped. Beeping occurred when switched on after Fuji installation and our quick startup guide suggested removing all USB connections which we did and it worked. Now that doesn't work so is it possibly the RAM and if so what do I do next?

Beginning to tear our hair out - help us to save our scalps. Jane

Being helped HERE.