Recommended to buy a Graphic Card

I think that with that small power supply you are going to have problems finding a graphics card that doesn't tax your system too heavily.

I can't recommend a specific model in your price range, but I would go for an Nvidia card. They tend to use less power than Radeon GPUs. Perhaps someone more familiar with Nvidia cards in your price range will see this thread and comment.

Upgrading the PSU will definitely improve the range of GPU cards that you can consider buying. The problem is that that is a Dell system you're working with, and it may not have a standard power supply slot in the case, or a standard ATX power supply pinout to hook to the motherboard.

Trying to upgrade components in a manufacturer's PC is difficult at best, because PC manufacturers use proprietary connector pinouts and peculiar parts that you can only get from them. It makes it really hard to get stuff that fits and works.

If you can find a power supply that will fit the case and has the appropriate connectors that fit, then by all means, an upgrade to a 500W supply is a good idea.

If you really want to improve that Dell, get the fastest CPU that motherboard supports, and max out the memory with the most it can support.

Or just start saving money to build your own PC.

Which version do you have ? The full tower or the smaller one ? There are 3 versions.

OptiPlex 380 Desktop Details | Dell

HN7XN Dell OptiPlex 380 0HN7XN Motherboard Overview - YouTube

And please put your proper operating system in your specs please :)

You can put in a Core 2 Quad or Core 2 Duo E8400 or E8600 and buy a GeForce GTX 950 or GTX 750 Ti and call it a day. Also we'll need to know what form factor it does come because it comes in three variations.

Well I recommend EVGA, not sure if it`s available in your area.

There`s an option to change the location at the top right of the site.

EVGA - Intelligent Innovation - Official Website

But you really need to add more memory along with a new card, more memory will help the video card.

You'll be fine with a GTX 950 and a 500W Power Supply