You shouldn't have any problems in theory, but we all know about theory don't we?? It's all relative. If you have another card try it in the CF slot. If it acts the same way then it is a problem with the slot. Call Dell and repot it. If it doesn't act like the previous card then it is the card itself that is causing problems. If you have access to a reader or another device that uses the card, test it.
See this thread for problems I am having:
My CF Card problem