Is PCA same as Orthdox?
Well both the OPC and PCA share the same commitment to Scripture and conservative doctrinal tenets, including creeds such as the Westminster Confession...I know that PCA is larger though in numbers and is more “mainstream” —meaning we encourage crossing denominational “barriers” and actively engage with the greater Evangelical world. I think we also put more emphasis on evangelism and missionary work than OPC does.
Is PCA same as Orthdox?
No. Different histories. Going from memory here, so my dates might be wrong. The OPC split from the Northern Presbyterians in 1936, the PCA split from the Southern Presbyterians in 1971. The OPC was originally the "Presbyterian Church in" (or of, I forget) "America". The main church sued over the name, and it became what you see now.
Lemme see....