Performance with HHVM on Apache and nginx

Question

I had a new Ubuntu server, and I want some opinions on the web server. I am developing with PHP, and stuck between Apache and nginx. I have used WAMP without problems, but in this case, I want to maximize the performance as much as I can, (by performance I mean nr. of simultaneous requests and time per request).

Here's my findings: nginx has a smaller memory footprint, also a smaller connection overhead, having superior performance in static content, and in lower-end machines.

Apache has more connection overhead, but is faster at PHP, because it is more "connected". I am not sure how HHVM will do on it though. It is also easier to configure with dynamically loaded modules.

I've also heard about the hybrid setup, using nginx as the static content server and route PHP to Apache.

Regarding my use case, I am using it as a web server, personal file server and a development server. I am using a MVC framework with a user management system, which seems dynamic to me.

Questions: With correct configurations and much stronger hardware, will Apache outperform nginx in number of simultaneous connections? More specifically, which of the 3 options should I use?

Please also include required configurations since they make big differences. Thank you very much.

Here's my physical setup:
Intel i7-4790
8GB DDR3 RAM (going to 16GB soon)
250GB SSD for applications and web server content
1TB HDD as secondary storage/backups
Ubuntu Desktop 14.04

Here's my (planned) setup on top of the web server:
HHVM
MySQL or MariaDB
PHP APC or Optimizer+
Varnish
Redis

Answer 1

I've decided to use nginx which beats Apache hard in the number of simultaneous connections.

Comparing with nginx+Apache, using nginx only reduces the complexity of the system, which makes troubleshooting simpler.