Some people don't have a mfaktc compatible graphic card.
As i'm able to do your assignement in minute, while on cpu it may take some hours. we get ' our' fun, you get yours.

I run mfaktc on GT440 card....cost me $100 or so, takes 11 hours to do a 79-bit TF....bought that card because it was the largest my 390W power supply would support. I'm working on a GT480, which looks like it might give the 440 a bit of an inferiority complex....

Checking out the following for 82 to 83 bits:
3321928171
3321928241
3321928307
3321928319

factor=0,3321933551,78,?
Testing GTX480 for temperature response.

GTX480 seems OK on 3321933551, will take it to 81 bits. Will report results Thursday.
factor=0,3321933397,30,81 (validation test; should find a few already-known factors)
factor=0,3321933541,78,81
factor=0,3321933451,78,81
factor=0,3321933389,78,81
factor=0,3321933367,78,81
factor=0,3321933361,78,81

Taking 3321933113 from 78 bits to 81 bits.

Luigi

taking the last 3 at the 71 level


3321935689, 71, 72
3321935833, 71, 72
3321935861, 71, 72


Grant.

I'll take the following:

Factor=0,3321935569,72,80
Factor=0,3321935689,72,80
Factor=0,3321935797,72,80
Factor=0,3321935833,72,80
Factor=0,3321935861,72,80
Factor=0,3321935891,72,80
Factor=0,3321935963,72,80

-- monst

Monst, the candidates in the 3321935xxx range are set aside for non-GPU use.

Sorry about that. I will stop crunching on that range. Here are the results I have up to this point:

no factor for M3321935569 from 2^72 to 2^73 [mfaktc 0.17-Win barrett79_mul32]
no factor for M3321935569 from 2^73 to 2^74 [mfaktc 0.17-Win barrett79_mul32]
no factor for M3321935569 from 2^74 to 2^75 [mfaktc 0.17-Win barrett79_mul32]
no factor for M3321935569 from 2^75 to 2^76 [mfaktc 0.17-Win barrett79_mul32]
no factor for M3321935569 from 2^76 to 2^77 [mfaktc 0.17-Win barrett79_mul32]
no factor for M3321935569 from 2^77 to 2^78 [mfaktc 0.17-Win barrett79_mul32]

I'll take the following instead:

Factor=0,3321928697,79,82
Factor=0,3321928699,79,82

-- monst