Modded PC power supply for charging

alright i know this is old but i need to ask will. will my 300w ATX power supply be enough?? it puts out 10 amps at 12 volts and at 5 volts 24 amps. i want to get this hyperion charger ; http://www.maxamps.com/EOS0610i.htm would it be good or would i be pushing it?? the most biggest packs i will use are 8000mah and maybe 10000mah if i parrallel up my 5s1p batts taht i ordered.