Hmmm....

You should not have latency issues with a card like that... You're using the ASIO drivers right?

Try possibly changing the PCI slot that it's in.. as it may be trying to share resources (IRQ) with another card.

Usually this sort of thing happens if you have a ram or disk bottleneck...
You said your box was foobarred recently right? Did you have to reinstall?

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Whoops... way for me to suggest what's been said before :)
That's what happens when I hit reply but don't write anything for a bit lol