When you are charged and if you are convicted of a DUI in Oregon, arrests and convictions in other states can affect the consequences here in Oregon. Not all states call DUI the same thing; there are DUIs, DUIIs, DWIs, etc. The state of Oregon will look at the elements of the crime of conviction in other states to determine if they match the elements of a DUII charge in Oregon.
If the elements are the same, Oregon will consider your conviction in the other state as a prior for the purposes of determining punishment and license suspension issues. Other factors, such as if your prior conviction was with the advice of counsel also may affect what happens here in Oregon.
So, the short answer is, yes a prior conviction for DUII, or an equivalent crime, in another state will affect what happens here in Oregon.