I'm far from an SPS or upgrade  expert but I never, ever recommend anyone
do an in place upgrade. For one, your entire farm  is down for the
duration of the upgrade and if you have a problem you don't have an exit
strategy short of restoring everything. The database  connection option
is good if you have new hardware, but since you tried an in place also
I'm not sure how your setup is. My recommendation is to do a Gradual
(also called side-by-side) upgrade. 530 is big, but not too big.
Gradual lets you break it into bite sized chunks and gives you a few
options if something goes wrong.

If try the gradual and you have problems post the errors  here.