poor disk performance with vista and dell xps gen 4 raid 0

[Guest]

Hi! I have a Dell xps gen 4 3.46 ghz 3 gig memory Nvidia GeForce 8800 GTX
raid 0 made of two 250gig drives.
I've upgraded from XP to Vista Ultimate. I have defraged, chkdsk, and made
sure all drivers were updated. The Windows experience index shows 2.5 because
of the primary drive (disk data transfer rate).
My pc now is EXTREMELY slow. It seems to be the disk drives which I've never
had a problem with.
Does anyone have a suggestion or idea as to why the performance may be so bad?
Is there an issue with Vista and Raid 0?
Any help would very much appreciated!!!!!
Thanks
Bill

 

[R. McCarty]

What interface technology are the two drives ( PATA or SATA ) ?
What operating mode are the drives using ( UDMA __ ) ?
Have you used any benchmarking tools to actually measure the
Access Time, Burst Speed and the like ?

I use the following to determine basic operating conditions:
http://www.geocities.com/vgrinenko/DiskSpeed32/

You say your drivers are up to date - does that include the nVidia
Chipset driver for Vista ?

 

[Guest]

The interface is SATA.
I already made sure I had the latest drivers for the Nvidia for vista.
How do I check the operating mode for udma?
I try a benchmarking tool.
Thank you very much.
Any more help will be appreciated.
Bill

 

[R. McCarty]

Just to clarify a point, when you say drivers for the nVidia - are you
referring to the Video card or the Chipset and the Video card. They
are a different set of drivers.

Normally, a RAID controller has a setup similar to BIOS setup. A
certain keypress at boot when the controller POSTs (Power on
Self-Test) takes you into the setup routine. From here you should
be able to see devices connected and parameters about them.

SATA Mode II (300 Mbps) should run at a UDMA mode of 5 or
greater. Using DiskSpeed32 the array should test at around 80 Meg
per second. (Average). Especially if the drives use perpendicular data
orientation.

Sorry I can't provide more exacting help, but there are just too many
variables at play that can affect/impact disk performance.

 

[Guest]

Thank you very much. I really appreciate the information. I've downloaded
Diskspeed32 and will soilder on!
Thanks again
Bill