Thread: OBD bookmarks
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Old 2020-08-23, 16:21   #5
kriesel
 
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"TF79LL86GIMPS96gpu17"
Mar 2017
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As I understand it, Factor5 is not as fast as Ernst's Mfactor program on the same hardware. And mfaktc or mfakto are much faster on a reasonable gpu (or even somewhat old slow gpu) than either of them on a normal cpu.
Mfaktc can go to almost 232 exponent, 95 bits factor, which seems more than enough for gigadigit candidates currently. Mfakto almost 232 exponent, 92 bits factor, also seems enough.
Mfactor compiles in different variants, for speed, depending on available processor type and how much multiple precision may be needed, for very large exponents such as in the middle of https://www.mersenneforum.org/showpo...04&postcount=5 (some 66 to 127 bit exponent examples)

More info on software capabilities at the attachment of https://www.mersenneforum.org/showpo...91&postcount=2
Not intending to bash anyone's software or efforts, but there's a reference thread on Factor 5 at https://www.mersenneforum.org/showth...126#post532126 which advises using mfaktx or Mfactor instead for speed & cost when practical.

Last fiddled with by kriesel on 2020-08-23 at 17:06
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