I had a similar problem after buying a brand new card. I uninstalled all the previous drivers and following advice from forum members, went to various sites to downlaod newer versions - they were all worse than the ones on the installation disk. So I stuck with them. There may be something to learn here - I did!
(a) Use add/remove programs (you should see the Driver listed.
When you install a new Driver, Windows will issue warning stating that it has not been certified. This is because the Driver has not been submitted to Microsoft for approval. Evidently this is an expensive and long winded process, therefore some manufacturers don't bother. All you need to do is check the ignore box, and then install the new driver.
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