Core i5 Temp over 53c... Is this normal?

[Lnx2Mac]

If you decide to get another cooler, make sure you get Arctic Silver thermal paste with it. The paste that comes with most aftermarket coolers is usually garbage and it's worth it to put the good stuff on there.

Unless you get a quality Cooler...
I more than strongly recommend the Scythe Mugen-2 Rev.B (or the Scythe BigShuriken for low profile cases), or a Noctua (though these are extremely expensive)...
You can safely use the compound (paste) that's provided with these...