Edius NX, Edius 4 and Xplode Pro, problems, help!

[Ulisse]

Hi, I have just assembled a new PC but I have many problems with Edius 4 and Xplode Pro. I use Sony FX7 HDV camera to shot.
I make an example.
If I drag a 30 seconds file on the Edius 4 timeline and I cut it on the midway some Xplode Pro transitions work fine and in realtime but some even don't work at all. I see thetwo clips withour transition.
Then if I use Xplode for Edius, on the Edius monitor I see green only.
I am worried and Saturday I'd like to format my HD but I am worried I will have the same problem.
Thanks for your info.

This is my config:

Pc-CONROE 6600 Core2Duo 2,4GHz Middle Tower Black
Scheda Madre: P5W HD DELUXE
MICROP. CONROE E6600 2,40GHz FSB 1066 4MB cache LGA775
RAM: 2 GB KINGSTON DDR800
SCHEDA VIDEO: SAPPHIRE RADEON X1950XT 256MB GDDR3
ALIM: ENERMAX INFINITY 620W
MASTERIZZ: PIONEER +/-R101
HD: 1 SATA DA 160 GB-SISTEMA
HD:2 SATA DA 160 GB RAID 0
HD:2 SATA DA 250 GB RAID 0
VENTOLA ARCTIC COOLING 12Vdc 120x120x25mm TACHIMETRICA
VENTOLA ARCTIC COOLING FREEZER 7 PRO X P4 SOCKET 775
Case full tower Cooler Master CM Stacker case