its difficult to say about thermal paste as i cannot physically see. generally, you dont need a huge amount of paste - just a blob per core i learned. i highly reccommend you sort this issue out before overclocking though. will the fan turn up any more?
Edit: i7-930s run hot, but that is actually a bit hot even for an H50 with stock core. Check your thermal paste! It should drop another degree or two once the thermal paste completely sets, but that takes a while