The OEM can tinker with the settings so nothing is amiss yet. The problem with OEM is you can't be sure what it is unlike the retail versions. It slams those new to OEM versions when they find something missing or broken.
As you know, issues and questions about OEM versions go back to the OEM company. This has upset some as MSFT won't do much with these versions.
So back to the place that sold it to you and ask what they did to it.
Just did a fresh install of XP Pro SP2 (OEM) on a fresh hard drive. (See the reason here http://forums.cnet.com/5208-6620_102-0.html?threadID=369818&tag=forums06;forum-threads fourth paragraph)
After the install I installed SP3, and nothing else. No AV, no nothing, just XP. Then went to the Windows update site and let it do its thing, and it came back saying no updates needed. 'Scuse me!! No updates!!?? Should be at least fifty or more. I've lost count of how many times I've installed XP in all flavors and they all have needed the latest updates after the install.
On another note, all these installs have wanted to activate. Not this one! It's a legal OEM copy and my Ethernet was plugged in during the install. But it did not even mention activating. And the Activate link in the Start, Programs, Accessories is not there either.