server_

You mean 94 Mbps* and NO you dont have the best ISP in Europe (i have 150 Mbps fiber-optic) and NO the problem doesnt seem to be your client... For some reason i dont get the part with "Windows ran out of memory". You mention you have upgraded your Windows from 7 to 8.1 and you have 8 GB RAM so even with max cache of 1.8 you should not see this warning msg, so im thinking maybe you have installed 86 bit OS instead of 64 bit one and prbbly this is the reason why you ran out of memory ... If that is the case just pre-install Windows 8.1 64 bit to use all the memory ... Regards, server_