SYNOPSIS
nvclock [options]
DESCRIPTION
This manual page documents briefly the nvclock command. NVClock is a
small program for tweaking nVidia videocards on FreeBSD, Linux and Win-
dows. Originally it was only meant for overclocking but these days it
can do much more. For instance it contains hardware monitoring support
using which you can view the temperatures and fanspeeds on cards that
support it. Further it allows tweaking of OpenGL settings using the
NV-CONTROL extension supported by the nVidia Linux/FreeBSD drivers.
OPTIONS
The program follows the usual GNU command line syntax, with long
options starting with two dashes (`-'). A summary of options are
included below.
--b, --backend backend
By default NVClock uses its so called 'low-level' backend for
reading and adjusting the clockspeeds of cards. Since NVidia
driver 1.0-7667 the drivers also provide an overclocking mecha-
nism called 'Coolbits'. It is only supported on desktop versions
of the GeforceFX/6/7. The main advantages it has over the low-
level backend is that it allows you to set the clocks to use in
2D and 3D programs. The problem is that various modern
GeforceFX/6/7 cards run at different clockspeeds depending if
you are running a 3D application or not.
Possible values for backend are: coolbits, coolbits2d, cool-
bits3d and lowlevel. The default option on GeforceFX/6/7 cards
is coolbits which sets the same clocks for 2D/3D, further cool-
bits2d and coolbits3d set respectively the 2D and 3D clocks and
finally lowlevel lets you use the lowlevel backend.
-c, --card number
Most systems only contain only one videocard. On systems with
multiple cards, this option can be used to select the card to
overclock.
-d, --debug
Enable/Disable overclocking related debug info. This information
shows the data stored in the PLLs during various operations.
-D, --Debug
Print a long list of GPU registers containing their current
value. All this info is very usefull for debugging.
-f, --force
Force support for a card that is currently disabled. Cards can
be disabled by default if the code for them is experimental or
in case a Laptop is being used. Laptops are disabled for safety
reasons as overclocking on them is more dangerous. In case you
Note that the duty cycle is NOT the fanspeed. The duty cycle
controls the percentage of time in a fixed time interval in
which the fan is 'on'. By choosing a higher value the fan is
enabled a larger part of the time which results in a higher
fanspeed. Changing the duty cycle from 20% to 40% doesn't double
the noise or fanspeed.
-i, --info
Print detailed card info
-m, --memclk speed
Memory speed in MHz
-n, --nvclk speed
Core speed in MHz
-P, --Punit mask
The Geforce6/7 are designed in such a way that one single GPU
can be used for creating different types of boards. For instance
they produce a NV40 (6800-class) GPU and when the GPU is func-
tioning properly they turn it into a 6800GT/Ultra or when some-
thing is damaged or when it can't reach high clocks they call it
a 6800NU/LE. The same is the case for NV43 based 6200/6600
cards. A 6800LE card ships with 8 disabled pixel units and 2
disabled vertex units. On various cards it is possible to re-
enable those units and if it works correctly it can greatly
improve 3D performance. The problem is that some units can be
broken which results in artifacts or instability. Further not
all GPU models can be unlocked either because Nvidia protected
the GPUs against modding or because there are no extra units to
enable.
Using this option you can enable extra pixel units. First check
using the -i switch which pixel units are masked. If none are
masked it means that none can be unlocked. For an explanation I
will take a 6800LE as an example which by default has 8 of its
16 pixel units disabled. The -i option showed the mask '1100'
which means that the first and second block of pixel units are
disabled. One block of pixel unit contains 4 pipelines in case
of most boards with the exception of NV44/NV46 which use 2 pipe-
lines for each pixel unit. To enable the first and second pipe-
line use -P 1111 (binary) or i you prefer hex 0xf. NVClock will
then try to unlock the pipelines note that even when there are
masked pipelines some can be locked in hardware so that they
can't be enabled.
-r, --reset
Restore the original clockspeeds
-s, --speeds
Print current clockspeeds in MHz
ing option is the same as the pixel unit one with the difference
that one bit corresponds to 1 vertex pipeline instead of multi-
ple. Again check -i to see which vertex units are locked. On a
6800LE you might see '001111' which means that the fifth and
sixth unit are locked. To enable all units use -V 111111
(binary) or 0x3f (hex). Note that it isn't certain that a unit
can be enabled as on some cards units are locked.
Below is a list with Display / OpenGL related options
-l, --list
List OpenGL / Display options supported by your chipset/driver
-q, --query option
Query current setting for one of the options listed under OpenGL
/ Display options.
-a, --assign option / option[display]="value"
Set a value for a supported option.
For OpenGL options like fsaa the following syntax is enough:
nvclock -a option=value
Display specific options like Digital Vibrance sometimes need
the display name: nvclock -a vibrance[crt-0]=value.
-x, --xdisplay
Choose another X display
-h, --help
Show summary of options.
AUTHOR
This manual page was originally written by Wouter de Vries
<sax@debian.org>, for the Debian GNU/Linux system. Later on it got an
update by Kel Modderman <kelrin@tpg.com.au> and at last it got rewrit-
ten for inclusion in NVClock 0.8 by Roderick Colenbrander <thunder-
bird@linuxhardware.org>
0.8beta2 NVCLOCK(1)
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