Thanks for your offer, Zak!
First, download the binaries from
here.
Unfortunately, there are no binaries for the Core2 yet. You could try those for the P4 (it should be quite irrelevant which specific, I guess) and/or the Athlon binaries.
Then create a text file in the same directory, with the following contents:
512697074397868507464830992105855089664575695425522835992747470881488640052598076608364916264171931518711016452728463454015615930496173963179151714060127379851269343356435328168074844330850160596351576082971234903468258958205452547120425573322600440367004964883936437287906385278156561312381803353061
Afterwards, execute the program as follows:
ecm 1000000 < [textFile]
Where [textFile] is the name of the text file. It should run for 2-4 minutes.
Please do this twice and report back the output.
Compiling the sources would be best, but involves quite some
manual work. Since this instruction, GMP and gmp-ecm have improved, you'd need GMP 4.2 and gmp-ecm 6.1.1
If you want to try it, I'm confident you'll get enough feedback from the
forum to solve any problems in your way.