We also run OS/2 on P1's, P2's and P3's in native mode. We have encountered no real problems associated with machine speed. I was trying to answer the question as given. Actually, I don't particularly like our EA software under Virtual PC2004. But I don't know PrismUp. Advantages of Virtual PC: No screen driver problems. Can turn printing on and off easily. Reduced number of halts in the EA programme (which is why we have one mass spec under Virtual PC). Possible advantage: Back up entire virtual machine to DVD, instead of just data. Restore machine disc, fire it up and extract data. I seem to remember no CD problems. Disadvantages: Slow. Molluscan. No access to external directories (outside the virtual machine). It seems on ours that the latest version of OS/2 supported by the EA software is younger than the earliest version of OS/2 supporting machine extensions. But I believe this is fixable. Hil -- Hilary Stuart-Williams PhD Research Officer - Stable Isotopes Environmental Biology Group Research School of Biological Sciences The Australian National University Acton, Canberra Australia ACT 2601 ------------------------ Office 61 02 6125 2099 Fax 61 02 6125 4919 Mobile 0421 905 478