Download and install CPU-Z. Run it and click the "Motherboard" tab. It will tell you what graphics interface you have.http://www.cpuid.com/softwares/cpu-z.html
However, it will not tell you which version of PCI-e the motherboard has; v1.0, v2.0 or v2.1. If it has a PCI-e port. If you do have a PCI-e port then you can install the HD 5670. However, be cafe and buy a HD 5670 that is PCI-e 2.0, not PCI-e 2.1 bacause PCI-e 2.1 has compatibility issues with the older PCI-e 1.0 slot.