Help PLease

When i'll join a game ( not only hmx or zm ) S&D , T&D any room , my loading page become black for 1 minute than i can't join the game.From 6 months , i have this problem. I sended many tickets , i created many post , but i can't solve this problem.Can you help me please if you know ?

My PC : AMD Athlon 64 * 2 Dual Core Processor 4600+, 1.0 Ram , NVIDIA GeForce 8400 GS ,Vista Home Premium 32-bit SP2 , 2.40 GHz , 320GB SATA , 1GB DDRII , Double layer.