I have seen this error in more than one notebook and models , basically it has something to do with expansion cards in your system , anything that is attached to the system board , Wlan mini card , bluetooth chip , memory chips , hdd , i had two cases in which the Wlan card was the bad guy that was causing all this , start with removing this Wlan card and see , actually when it says "Memory parity check error " it's almost always has nothing to do with the memory!!

I am having the same problems (and more) with my Inspiron 1720.  Bought it in November 2007 but didn't really start using it heavily until March 2008 - way after the 21-day warranty was up. 

Get Hardware Malfunction / Call your hardware vendor blue screens all the time.  I've been on the phone (an hour eachtime) with Dell service 10+ times since January 2008 and the year-warranty is over November 2008. 

Service has had me make changes to software, have taken over the laptop remotely, have (twice) sent a tech out to repair the machine, have sent me 2 memory cards so I could put in the cards while they directed me over the phone, and - finally - decided it must not be hardware, it's software - so they had me wipe out the complete system and rebuild.  I really enjoyed that one!

Anyway, within minutes to a few days, every time, I got the blue screen again.  I've asked for a new replacement laptop, hoping they would back up their equipment, but - no, no replacements after 21 days.

I am not a computer geek, I don't know about video cards being reseated or upgrading drivers ... I just want my laptop to work ... normally ... what was offered in the advertising.

EllenMac

Error often caused by a driver issue

http://www.mypchealth.co.uk/GuideParity.php

I am having the same problems (and more) with my Inspiron 1720.  Bought it in November 2007 but didn't really start using it heavily until March 2008 - way after the 21-day warranty was up.    Get Hardware Malfunction / Call your hardware vendor blue screens all the time.  I've been on the phone (an hour eachtime) with Dell service 10+ times since January 2008 and the year-warranty is over November 2008.    Service has had me make changes to software, have taken over the laptop remotely, have (twice) sent a tech out to repair the machine, have sent me 2 memory cards so I could put in the cards while they directed me over the phone, and - finally - decided it must not be hardware, it's software - so they had me wipe out the complete system and rebuild.  I really enjoyed that one!   Anyway, within minutes to a few days, every time, I got the blue screen again.  I've asked for a new replacement laptop, hoping they would back up their equipment, but - no, no replacements after 21 days.   I am not a computer geek, I don't know about video cards being reseated or upgrading drivers ... I just want my laptop to work ... normally ... what was offered in the advertising.   EllenMac