Good comp + SCSI = crap ?

OK, here is the situation:
P650 3.4Ghz, ABIT AA8XE mobo, 2Gb RAM DDR2, 680Gb on 3 HDs, printer, 2 printers on USB.
And Adaptec 2930U SCSI card, with Canon scanner FS4000US on it.

The problem: every time I click on Windows Explorer or MyComputer, it is searching for something and I can't see any of HDs (nor DVD). It takes about 4 minutes until Windows Explorer displays the list od drives in Folders. After that things are OK, access is fast, but after closing Windows Explorer the situation repeats itself: another 4 min. for the comp to sort itself out.
OS is Windows XP.

What gives ?
I know that SCSI devices can be pretty nasty, but the scanner only has SCSI and USB1 ports, so I would really like to have it on SCSI.

The Windows installation is a clean one, the comp is 1 day old...so I am sure I haven't screw up anything, apart from installing the devices: 2 printers and a scanner.

 

how are your hard drives configured? what brand, type and how big are each of them? are they SCSI as well?

also make sure both the SCSI card and scanner are terminated and IDed properly

 

No, the only SCSI device is the scanner. I guess it works equally well whether it is terminated properly or not.

Having said that, I have found the problem. Yje problem is the printer MPC190 (printer/scanner/copier all-in-one).
I have tried reboot the computer with various devices disconnected, and when the printer is Off then all works OK. As soon it is back On, then all slows down to unworkable level. Switch the printer Off and restart the comp - all is back to normal.

I had some problems with installing MPC190 on the old comp too. I guess it is something with the driver maybe ?

At any case, I will just hook it up to the old comp where it appeared to work reasonably well. The new comp just doesn't dig it...

Of course I will try any suggestions, but it appears to me that it may be difficult. XP says all devices are working properly etc. except that Windows Explorer is sooooooooooooooooooooooooooooo slow - basically you can't use the comp.