Problem with ghosting using DVI to VGA converters

[XLV]

I wonder if anyone has faced similar problem.. the systems are three athlon64 of various configurations, all using nvidia geforce 6600gt pci-e graphics cards, which are from Prolink (two of them) and MSI.. I tried before I bought the MSI to use a dual-dvi Gainward GF6600GT, assuming that after some time in 6600GT production, this may have been solved, especially in dual dvi cards... but the problem existed, so I returned it.. the monitors are two Eizo F931 21" and one Philips Brilliance 201B 21".. ofcourse the same monitors on same cards work well when connected to the VGA connector of the cards... The DVI to VGA adapters used are the ones that where included in the package of the graphics cards. Maybe there are some others (such adapters) available, of better quality, to remedy this?