Power sources for tier 2 TSS armor

I am finishing up on my TSS tier 1 set of armor (casual player) I only have arms and chest left to complete the set. I am going to be moving to step 2 and that is to get the power sources i need to finish them up and move to TBS armors. Anyway the meat and potatoes of what i am after is ya'lls experience of mobs that drop the power source and how complicated they were from least to hardest. Also if anyone has experienced it....in Vergalid mines (sp?) I lag out like crazy! I can go anywhere in the TSS expansion but if i go in there i lag out so badly that i go ld or am SEVERAL seconds behind what is actually going on...and then go LD lol. Anyway if anyone has any pointers on how to square that away i would appreciate it. As current the only place i can really go to hunt the power sources is Valdeholme (once again sp?) and i think those may be a little to much for me to tank atm 13,800hp 2400ac. Anyway any tips or advice would be much appreciated.