I asked a question a while ago about learning to use Linux, and since then I've installed CentOS 5 on a local machine to match my host.
Installation was fine, and I'm up and running, but I can't setup it up to use 2 monitors (Dual Heads) and I just can't cope without 2 monitors.
So is anyone using CentOS with 2 monitors? And if so HOW?
CentOS 5 GNOME 2.16.0 nVidia 8600 GTS
Did you pick CentOS for a reason?
I ask because, if I remember correctly (and I used this distribution briefly), it is essentially redhat linux enterprise edition, but forked and updated from that distribution (to provide a free version of it). You probably would only want this distribution for something you need a stable server for.
As a desktop linux environment, I would highly recommend Ubuntu... things just tend to work on it (for the most part), and there is a highly active community with many forums you can search for problems on it.
I have set up 3 laptops and 1 server on Ubuntu, 2 laptops had issues but were resolvable via googling for forum responses, another high end laptop had no issues, and the "server" was a home server and was kind of old with pretty bland hardware, so no issues there.
At work, I am using Ubuntu with dual monitors and it works just fine, I don't think with any special configuration.
I know this doesn't really answer your question, but if you are using dual monitors it seems to indicate to me that CentOS might have been a somewhat suboptimal distribution selection. For cutting edge support on the RedHat distribution suite, you might consider Fedora, which is where they put all the newest stuff (which is more likely to support things like newer hardware)... but again, I think Ubuntu is a distribution you should consider.
You'll need to use the nVidia proprietary driver to get dual-head support — the free
nv driver does not do dual head. The nVidia driver comes with a long
README file, take a look at the TwinView section of it.
In this case, you have a couple options. You could dual boot CentOS and Ubuntu... have one partition for CentOS root (/), another for Ubuntu, and then another for home (/home), thus all your custom data is mounted the same on both setups... though you might want to specify different users for the 2 so your dotfiles don't get mixed up between the 2.
Alternatively, you could run in Ubuntu, and then run CentOS as a virtual system... I've never done it personally, but we use virtual PCs a lot at work (I'm pretty sure there are some free virtualization software around).
However, I would say you shouldn't worry about duplicating the environment perfectly. There are bugs and inconsistencies between distributions, but in general, if you are using the same applications (Apache, MySQL, PHP, Tomcat, whatever), then the distribution shouldn't have much of an impact on being able to replicate the environment.
The only thing you might want to take care in, is making sure they are configured similarly... but it's not that big of an issue if you test on your dev system, then do sanity checks on your hosted system. Typically, the programming environments isolate you from system differences.
Well I'm on CentOS 5.2 here using dual monitors. Here is my xorg.conf. I'm using the NVIDIA driver
EDIT: You can use nvidia-settings to configure then generate an xorg.conf for you. Also the README provides very detailed information.