Insufficient Material

http://www.chess.com/livechess/game.html?id=223049304

This game was drawn due to insufficient material when white ran out of time. Can anyone explain why?

I know it is very difficult for black to win, but it is possible.

With best play by both sides, the game is drawn.

p.s. Obviously, helpmates are still possible.

That's pretty close to OTB rules but on the internet, it's different. Players don't have access to the arbiter and therefore claims of "trying to win by unusual means" fall on deaf ears. It's a compromise solution, I think.

Anyway, Chess.com has a long list of (mostly minor piece) endings, that can give rise to helpmate wins but are adjudged as drawn, by insufficient material.

I'm a bit confused.  Why was the game considered a draw for "insufficient material" after move 82 than on 80.Nxe6?  Material was the same in both positions.

I get the feeling that black just ran out of time in this situation, and it was considered a draw since white had insufficient material to mate (though technically, a pawn is enough to mate).

Exactly.

But White was the player who ran out of time, right (it was White's move when the game ended)?  So it doesn't matter whether White had sufficient mating material, only whether Black does.

See PrawnEatsPrawn's post up above (#7).  "Insufficient Material" is a misleading name for this draw as it more closely approximates claims based on the "not trying to win by normal means" (FIDE) or "insufficient losing chances" (USCF) rules.

The idea behind those rules is that, if your opponent doesn't have a reasonable chance of winning by "normal" means (i.e., executing a checkmate) and is instead just trying to run your clock down, you have the recourse of calling on the arbiter before your time runs out to declare a draw.  Since there are no human arbiters on the site, then as a compromise, there is an automatic declaration of a draw when time runs out under certain circumstances.  For ease of programming, they've placed all the "insufficient losing chances" circumstances in a list with the "insufficient material" ones so that it only has to check once.  Unfortunately, this leads to confusion such as what your are experiencing, here.

Interestingly, the position above is drawn because the white pawn is on the 4th rank - and is a Knight's pawn. On any other file, if the pawn were blockaded by a Knight then Black would have a theoretical (but difficult) win unless the pawn were further advanced. cite Of course, the board software may not take this into account.

It doesn't.  As I recall, it is a very simple listing.  Something like 'all positions where the side with time has only a king as well as a bishop, a knight, or two knights.'  I'm sure the exact list can be found somewhere, I'm just not inclined to go looking for it.

 In this very similar game, Karpov resigned.  It was his turn and he could not prevent the check mate.

I could not find the list of  "insufficient losing chances" and "insufficient material."  Is there a link?

And tbh that's plenty good enough for me. I've been revising B+N lately but don't expect to ever have to play it - should I ever end up with N+NvP then my lifetime average will just have to take the half-point hit. 

Thanks for the explanation.  By the way, it seems that both Topalov and karpov made mistakes in their game.

http://en.wikipedia.org/wiki/Two_knights_endgame#Topalov_versus_Karpov

Oh, I didn't catch that.  Thanks for pointing that out.