Upload troubles caused by forum software or dreamhost?



Hello everyone.

I’ve been using dreamhost for many years now and I never had any troubles with them.
Now I just bumped on a problem of my own which is currently unclear and that’s why I’m asking for some help.

At the moment I’m using the forum software SMF and I tried to upload a file around 150MB but it failed (Errors: ERR_CONNECTION_ABORTED, Internal Server Error, …).
I’m using custom php.ini and adjusted everything to 500MB and increased the execution and input time.

Since its still not working I’m wondering if this is because dreamhost has a limit on the shared server or would it be a setting?

Thanks in advance.