The MSDN article "Order Preservation in PLINQ" states:
The following example overrides the default behavior by using the AsOrdered operator on the source sequence. This ensures that the Take method returns the first 10 cities in the source sequence that meet the condition
var orderedCities = (from city in cities.AsParallel().AsOrdered() where city.Population > 10000 select city) .Take(1000);
Is it possible to return more (or less) than 10 first items ordered in PLINQ query and how?