I don't know how long this link will stay active so if someone can possibly dump it somewhere where it'll stay safe I'll say do it.
This version of Prime95 I find works better than Orthos and allows multiple cores in one instance instead of needing 2 or 3. I haven't tested it with a quad core yet so I don't know if it recognizes 4 cores, but it works awesome with 2.
New features in Version 25.3 of prime95.exe
1) Multiple LL tests can be run within a single prime95 instance. There is
no longer a need to run multiple instances of prime95 on multi-cpu
2) Uses a new version of the Primenet server. Features include user IDs that
are different than team IDs. New work types. Ability to set some client
options using web-based forms.
3) Communication with the server runs in a separate thread.
4) The CURL library is used for communication with the server. Hopefully
this will support a wider variety of client networking configurations.
5) Supports using multiple logical or physical CPUs on a single LL test.
Except for some hyperthreaded CPUs and only on some FFT sizes, this is
not recommended as you will get more throughput by giving each CPU
its own number to test.
6) ECM and P-1 now support B1 and B2 values above 4.29 billion.
7) Several files have been renamed so that they are not changed by Windows
save/restore. Prime.ini is now prime.txt. Local.ini is now local.txt.
Worktodo.ini is now worktodo.txt. The primenet.ini file has been
deleted - it is now a section within the prime.txt file.
8) It is now legal to put comment lines in the prime.txt, local.txt, and
9) In older versions, editing the worktodo.ini file while prime95 was running
sometimes had the desired effect. That is no longer the case. You can
create a worktodo.add file to add work to a running prime95.
10) WARNINGS: Previous versions of prime95 will not be able to read save files
generated by this version. This version will not be able to continue from
P-1 save files generated by the previous version in the middle of stage 2.
11) Program can now do PRP tests of k*b^n+c. Add a line worktodo.txt that
looks like this:
The optional how_far_factored (in bits) and tests_saved values are used
to determine if P-1 factoring prior to the PRP test would be beneficial.
12) The program no longer does a one-hour self-test before testing an exponent
with a new FFT length.
13) You can now copy the contents of a window to the clipboard.
14) New icon colors. Green means "go". Red means "stopped".
15) The torture test dialog box lets you choose how many CPUs or cores you
want to torture test.
16) The benchmark times both single-threaded and multi-threaded FFTs.
17) The Advanced menu no longer needs a password.