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What's New: New Features in Version 24.x of Prime95 |
1. A bug that caused the
torture test to hang on 256K FFTs on SSE2 machines with 128K of L2 cache was
fixed.
2. Celeron D (256K L2
cache) and Willamette (also 256K L2 cache) now have different implementations
for several FFT sizes. This results in an improvement of several percent for
the Celeron D.
3. A bug that caused some
machines to generate "Error 2252" when communicating with the server
was fixed.
4. SSE2 trial factoring
code had a bug when factoring very large exponents.
1. For SSE2 machines the
larger FFTs have been changed to more effectively use a wide variety of L2
cache sizes. The previous version was optimized for a 256KB L2 cache only. Depending
on your CPU and FFT size, you could see an improvement of several
percent.
2. As a side
"benefit" even larger FFT sizes are now supported. This allows
testing of exponents up to 596 million. Not recommended.
3. The factoring breakeven
points have been recalculated using my 2 GHz P4. This version of prime95 will
do less trial factoring.
4. Since server database
crashes cause spurious error 3 messages, prime95 will now ignore error 3
messages from the server for 72 hours. This should workaround the problem
whereby a result is reported but no CPU credit is given and the reservation is
not cleared.
5. Fixed crash bug trial
factoring exponents above 286 million.
1. Faster FFTs for AMD64
using prefetchw in both 32-bit and 64-bit mode. You can expect about a 15%
speed improvement.
2. Prime95 now detects
support for 3DNow! instructions. See undoc.txt for overriding this detection
with CpuSupports3DNow=n in local.ini.
3. Factoring entries in
worktodo.ini now accept exponents up to 2 billion.
4. Improved checking for
memory allocation errors during a torture test. Better guessing of amount of
memory to use in a blend test.
5. Added timeouts to
PrimeNet communications in hopes of avoiding rare hangs when contacting the
PrimeNet server.
6. Fixed rare bug where
P-1's GCD could miss a factor.
7. Added trial factoring
to the benchmark.
8. Fixed bug in ECM when
using zero-padded FFTs.
9. SSE2 macros optimized
for an additional 1-3% improvement on P4 and AMD64 CPUs.
1. 64-bit version of
prime95 available for 64-bit Windows.
1. Fixed crash when
running on machines with "no-execute" protection.
2. Fixed mis-detection of
some P3 and Celeron CPUs.
1. Athlon users should see
a 20% to 30% speed increase.
2. Pentium, Pentium II,
Pentium III users should see dramatically WORSE performance. Run version 23
instead.
3. P-1 and ECM now support
numbers of the form k*b^n+c. This cannot be done from the menus. Add these
entries to worktodo.ini:
Pminus1=k,b,n,c,B1,B2
ECM2=k,b,n,c,B1,B2,curves_to_do[,specific_sigma]