I have gigabyte ga-ep41-udl3 with 4 ddr2 slots can support every ddr2 ram and currently I have 2x2 2gb 800 mhz 5-5-5-5-15 I think it goes like that and when I add 1gb ddr2 ram 5-5-5-5-18 pc just doesn't want to boot up or it gives me blue screen etc..But I didn't know my motherboard is using dual channel memory so I am asking you guys I want to buy 2x2 2gb apacer 800 mhz and will my pc boot up then ?I mean if it doesn't I will go to the service so they can fix it but I just want to know without spending 10$ on service...Thanx anyway