No way a 8600GS can out perform a 4570. Maybe you confused the 8600GT's scores. The 4570 is a modern card with advanced power saving features compared to the older 8600 and if crysis was the goal for your notebook then both fail and you should consider a notebook than can accomodate a faster solution.
You can also add warranty from third parties such as square trade who will either repair your computer thru a depot such as micromedics (amex uses them) or they refund the cost of the notebook (not the cost of the warranty) if its unfixable.
the "Balanced Power Plan" option is also tweaked by many manufacturers by default since they will assume most people will leave the settings alone. its possible the gains you see are from the tweaks and switching out to the windows default reverts changes optimized by the companies we get the computers from. Dell and HP are prime examples of this.
The Dell M4400 uses an ALPS touch pad which is unfortunately a slower and less responsive pad compared to the synaptec used on the T500. If you plan on using a high resolution screen such as the 1920x1200 screen the ALPS is virtually unusable for gaming and a huge precision pain for anything else.