My question is how do I know what motherboard I have and what upgrades can I do to my computer like update memory and the graphics. What kind of memory and what grapics card can I upgrade too.

Motherboards have some sort of identifying information printed on them, although decoding the information can sometimes be a challenge. Where did the replacement board come from? If a manufacturer cannot be discerned from the printed info, a software utility such as CPU-Z may identify the board.

If the original Dell board is still in the system, all the specs of the system are listed in the support section of Dell's website. There is a Dell service code on a sticker on the system that can be entered on the website to access all the information for this specific system.

Once the board is identified, visit the board manufacturer's website and download a manual. It will describe all the features and limits of the board as well as what type of memory and the memory arrangements the board supports. Most any graphics card that will physically plug into the board can be used, however other system factors, such as power supply wattage and available connectors, may need to be taken into consideration as well.

Scleros I downloaded Belarc and this is my mother Board: Intel Corporation D845PECE AAC11812-103
And this is also the graphics card I got in my computer. Standard VGA Graphics Adapter [Display adapter]
I don't know if this will help you let me know what I have. I was looking in a few other forums and I was looking at a MSI nVidia GeForce 8400GS 512MB DDR2 VGA/DVI pci-e. Im just not sure if it will fit or what else I need to know before I spend a few dollars.

Take alook at your motherboard. What you're looking for is a PCIe slot.

After researching and looking at your motherboard I don't think yours supports PCIe Graphics Cards.

I could be wrong though. But from what I read and looked at, it cannot!

Sorry ITstudent Im not sure what a PCIe slot is. I wish I could take a picture of it and email you or post it

I just read up on PCI slots. If I'm looking at the right thing it looks like I have 3 traditional PCI slots and 1 short PCIe x4 slot. The traditional Slots are white and the 1 short PCI that my current Card is plugged into is black and a little short

Isn't the new one you are looking at PCIe?

Intel's D845PECE Technical Product Specification on page 15 does not show a PCI-E connector on this board. The short one at the edge of the board is a communications and networking riser (CNR). This board only supports PCI and AGP video adapters. Current video adapters suitable for meeting the technical requirements of today's 3D games are not produced in the AGP form factor, only PCI-E.

Intel Desktop Board D845PECE FAQs