playing chess a long time record

How many hours is the longest you have played chess in one day OTB.

My personal record is with one of the best in the club.

I played from 10 in the morning till 24 in the evening. 14 hours chess. we only had a break for pizza.

I think we played 20 games and I only won 4 games.

does somebody have experience playing 24 hours or more without sleeping - just playing chess?

Not OTB, but I did participate once in an online blitz marathon.  I lasted about 37 hours before folding.  My brain is still trying to recover from that one...

I did a little research the record for otb blitz marathon is 665 games without sleep or break.

Someone tried to break the record but fell a sleep after 510 games. it was 5 minutes games otb.

How long (time-wise) did that event last?  Let's see, avg 5-minutes a game, 665 games, divided by 60 minutes per hour = 55+ hours, or more than two full days...

I can not find how long it took but there is  a youtube video of the man who tried to break it. at the end of  video he falls a slee. the GM who made the record is mentioned in the video.

http://www.youtube.com/watch?v=dIbiFN4lC8Q

I took part in an event in South Africa a few years ago, where they attmpted to break the record. There were 5 or 6 strong players, playing blitz against many participating club players.

I think the event ran through 48 hours, and most of the strong players completed the time,  but the event was won by Jaco Nelson, because he completed the most games.

My understanding was that the record was indeed broken, but I don't know if it was ever ratified by Guiness, there might have been some issue with the opposition being too weak.