I need to do a search for a C129 first, but I'll take a whack at this for a few days or so. :smile:

My CUDA setup is dead (laptop power plug failed). I bought Xyzzy's 750ti, but it's in an ubuntu box, and he mentioned when I bought it that linux drivers weren't mature yet so I haven't tried installing CUDA on it.

If someone has info that says otherwise, I'll be excited to resume poly searching for myself and this thread after I get CUDA set up on the new card. A 750ti will be quite an improvement over a 460M, too!

[QUOTE=fivemack;379917]Hello all.

I've just done a moderately big GPU polynomial select for a C165, and, having trial-sieved rather more polynomials than I usually do, reached the slightly unexpected position where the 17th-best polynomial by Murphy_E was overwhelmingly the best by actual sieving yield.

I get the impression that Murphy_E is systematically larger for small leading coefficients; has anyone done empirical work on that scaling? Would it be worth trial-sieving a thousand polynomials on my next big GNFS job (this would be an effort about the size of the GNFS job) and seeing if I can quantify the effect?[/QUOTE]

Did any further conclusions ever come of this? This Murphy-E effect would explain why searchers in this thread routinely found "good" polys with tiny leading coeffs compared to the coeffs usually searched by the big guns/more seasoned factorers.

[QUOTE=VBCurtis;407923]My CUDA setup is dead (laptop power plug failed). I bought Xyzzy's 750ti, but it's in an ubuntu box, and he mentioned when I bought it that linux drivers weren't mature yet so I haven't tried installing CUDA on it.

If someone has info that says otherwise, I'll be excited to resume poly searching for myself and this thread after I get CUDA set up on the new card. A 750ti will be quite an improvement over a 460M, too![/QUOTE]

I have a GTX 750Ti working on Debian with the legacy nvidia drivers and some debian packages. CUDA and OpenCL are working fine. You should be able to install the same packages on Ubuntu but I don't know about the legacy Driver part.

These are my currently installed packages with *nvidia*, *cuda* or *opencl* for comparison. There may be some -dev packages that you don't need.
[CODE]dpkg-query -l '*nvidia*' | grep 'ii'
ii glx-alternative-nvidia 0.5.1 amd64 allows the selection of NVIDIA as GLX provider
ii libegl1-nvidia:amd64 340.76-2 amd64 NVIDIA binary EGL libraries
ii libgl1-nvidia-glx:amd64 340.76-2 amd64 NVIDIA binary OpenGL libraries
ii libgles1-nvidia:amd64 340.76-2 amd64 NVIDIA binary OpenGL|ES 1.x libraries
ii libgles2-nvidia:amd64 340.76-2 amd64 NVIDIA binary OpenGL|ES 2.x libraries
ii libnvidia-compiler:amd64 340.76-2 amd64 NVIDIA runtime compiler library
ii libnvidia-eglcore:amd64 340.76-2 amd64 NVIDIA binary EGL core libraries
ii libnvidia-ml1:amd64 340.76-2 amd64 NVIDIA Management Library (NVML) runtime library
ii nvidia-alternative 340.76-2 amd64 allows the selection of NVIDIA as GLX provider
ii nvidia-cuda-dev 6.0.37-5 amd64 NVIDIA CUDA development files
ii nvidia-cuda-doc 6.0.37-5 all NVIDIA CUDA and OpenCL documentation
ii nvidia-cuda-gdb 6.0.37-5 amd64 NVIDIA CUDA Debugger (GDB)
ii nvidia-cuda-toolkit 6.0.37-5 amd64 NVIDIA CUDA development toolkit
ii nvidia-detect 340.76-2 amd64 NVIDIA GPU detection utility
ii nvidia-driver 340.76-2 amd64 NVIDIA metapackage
ii nvidia-driver-bin 340.76-2 amd64 NVIDIA driver support binaries
ii nvidia-installer-cleanup 20141201+1 amd64 cleanup after driver installation with the nvidia-installer
ii nvidia-kernel-common 20141201+1 amd64 NVIDIA binary kernel module support files
ii nvidia-kernel-dkms 340.76-2 amd64 NVIDIA binary kernel module DKMS source
ii nvidia-modprobe 340.46-1 amd64 utility to load NVIDIA kernel modules and create device nodes
ii nvidia-opencl-common 340.76-2 amd64 NVIDIA OpenCL driver
ii nvidia-opencl-icd:amd64 340.76-2 amd64 NVIDIA OpenCL installable client driver (ICD)
ii nvidia-profiler 6.0.37-5 amd64 NVIDIA Profiler for CUDA and OpenCL
ii nvidia-settings 340.46-2 amd64 tool for configuring the NVIDIA graphics driver
ii nvidia-smi 340.76-2 amd64 NVIDIA System Management Interface
ii nvidia-support 20141201+1 amd64 NVIDIA binary graphics driver support files
ii nvidia-vdpau-driver:amd64 340.76-2 amd64 Video Decode and Presentation API for Unix - NVIDIA driver
ii nvidia-visual-profiler 6.0.37-5 amd64 NVIDIA Visual Profiler for CUDA and OpenCL
ii nvidia-xconfig 340.46-1 amd64 X configuration tool for non-free NVIDIA drivers
ii xserver-xorg-video-nvidia 340.76-2 amd64 NVIDIA binary Xorg driver
ii ocl-icd-libopencl1:amd64 2.2.4-1 amd64 Generic OpenCL ICD Loader
ii ocl-icd-opencl-dev:amd64 2.2.4-1 amd64 OpenCL development files
ii opencl-headers 2.0~svn28973-2 all OpenCL (Open Computing Language) header files
ii libcuda1:amd64 340.76-2 amd64 NVIDIA CUDA Driver Library
ii libcudart6.0:amd64 6.0.37-5 amd64 NVIDIA CUDA Runtime Library[/CODE]

Thanks, Christian! I've been meaning to move the card into my main system; your working setup encourages me to give this a go. Between CUDA-ecm and poly select, I miss having a GPGPU.

Just as a heads-up, I started at 100M and am currently passing through 102M or so.

Here's the best two I've found so far. Neither is really close to the expected e-value, but they may be worth trial-sieving:
[CODE]expecting poly E from 4.57e-014 to > 5.26e-014
R0: -137547131193043341793334930193270566
R1: 70224319209054721
A0: -48715040541374867514878224348681604586285
A1: -275708572214962467144881300531857095
A2: -397914309979816733185360998057
A3: -8084283143447552273377
A4: 607205817813118
A5: 101468208
skew 8049123.93, size 4.248e-018, alpha -6.525, combined = 4.117e-014 rroots = 1

R0: -137052228970709324982229261366831248
R1: 38784020496691787
A0: -44875760234631994289855676839471716527683225
A1: 26415950906429837100672340418747601895
A2: 1882671010943471032317074656115
A3: -187234878234320539666327
A4: -4219616160069306
A5: 103313520
skew 21539398.15, size 3.540e-018, alpha -7.329, combined = 3.696e-014 rroots = 5[/CODE]

I'm going to play around in the 500M range for a bit, and if nothing good shows up there, I'll drop down to a lower coefficient like 1M.

Here's the best in the 500-510M range:[CODE]polynomial selection complete
R0: -99597953807168680476889254921237040
R1: 155679631953907381
A0: -92612284320573352971113764845050011599172263
A1: -14544423142209256027253616209189318319
A2: 3861979188784232836840703659203
A3: 261460166847969497979769
A4: -19772402213056250
A5: 509724600
skew 12734708.51, size 3.757e-018, alpha -8.313, combined = 3.829e-014 rroots = 3[/CODE]

I'll try down at around 100M (and maybe 10M).

Here's a good one:[CODE]R0: -278041983541936879812937287512480720
R1: 83839300817041243
A0: -3390086640132698923491414956173048512425481
A1: 3738332722384494113415434782471399053
A2: -1160199637312567120662841930769
A3: -40839181952932892416147
A4: 1087473801891780
A5: 3006324
skew 32140665.92, size 4.576e-018, alpha -7.218, combined = 4.328e-014 rroots = 3[/CODE]

Still under the expected, but best score so far.

[CODE]polynomial selection complete
R0: -256712836882622622457839933429900183
R1: 61840577050423613
A0: 602093201366745363780865731715111641933619000
A1: 92059674952581867600427558954630776650
A2: -1195424019900556240035714699635
A3: -58210719595944209591027
A4: 330526880428891
A5: 4480740
skew 64846617.97, size 4.451e-018, alpha -7.480, combined = 4.305e-014 rroots = 5[/CODE]

Anyone like to have a go at finding a poly for this C154 from Aliquot sequence 829332:3589?

[CODE]4537787384062167229294057374468826821223279315636792016447006047185936215587115121338899234285565806951562459365575674996087301727915180317496191381025877[/CODE]

This would be most appreciated! Thanks,

Rich