How to get Nvidia graphics working on Sony Z laptop? I have an older Sony VAIO Z 590 laptop with switchable graphics between Intel and Nvidia GeForce 9300M. It is NOT Optimus. I did a clean install of Ubuntu 12.04. Everything works, but it's using Unity 2D with the Intel drivers. I've tried loading the Nvidia drivers from "Additional Drivers", but it says "this driver is activated but not currently in use".   When I run "nvidia-settings", an error window pops up to say "You do not appear to be using the NVIDIA X drivers." "lspci" shows both graphics cards. Let me know if I should add more info.  How do I get the Nvidia graphics and Unity 3D working?   More info:  $ lshw -short -class display  H/W path       Device  Class       Description ==============================================  /0/100/1/0             display     G98 [GeForce 9300M GS]  /0/100/2             display     Mobile 4 Series Chipset Integrated Graphics C  $ glxinfo name of display: :0 Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Error: couldn't find RGB GLX visual or fbconfig  Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0". Xlib:  extension "GLX" missing on display ":0".   Excerpts from :  [    16.373] (II) LoadModule: "glx" [    16.373] (II) Loading /usr/lib/x86_64-linux-gnu/xorg/extra-modules/libglx.so [    16.386] (II) Module glx: vendor="NVIDIA Corporation" [    16.386]    compiled for 4.0.2, module version = 1.0.0 [    16.386]    Module class: X.Org Server Extension [    16.386] (II) NVIDIA GLX Module  295.49  Tue May  1 00:09:10 PDT 2012  [    16.608] (II) NVIDIA dlloader X Driver  295.49  Mon Apr 30 23:48:24 PDT 2012 [    16.608] (II) NVIDIA Unified Driver for all Supported NVIDIA GPUs  [    17.693] (EE) Failed to initialize GLX extension (Compatible NVIDIA X driver not found)
How do I install the Nvidia drivers? I just ordered the Nvidia GTX card. I have a dilemma, though. Should I keep using the driver which is available in "additional drivers" in Ubuntu, or should I install the driver from the Nvidia site?  So which driver is the best for me?
How do I evaluate these fork() calls with the && and || operators in C? How accessible are the Stack Exchange sites for users of screen reader software? There are some plans to put more information on  which is a Stack Exchange site. I am concerned it may not be as readable to everyone as it could be on a plain wiki.  Is there any information on how to use Stack Exchange with a screen reader? How can I get a DisplayLink USB monitor work under Ubuntu? I have a DisplayLink-based external USB monitor, which has both power and data over USB, and seems to work perfectly under Windows 7, but only can display a text console under Ubuntu 10.10, and that I can only use when I am actually switched to it. So the only Use I can have so far is to have some text-based monitoring or console that I can watch while working on the graphic display.   I know there are some development done for DisplayLink, but I never could get it to actually run properly.   Yes, I tried the detailed setup described in other , but they did not work, and instead crashed my X that I had to restore.   Merci :-) I was trying to prove this inequality using induction, but couldn't do.  Question: Suppose $a$ and $b$ are real numbers with $0 &lt; b &lt; a$. Prove that if $n$ is a positive integer, then:  $$a^n-b^n \leq na^{n-1}(a-b)$$ How does one know when to use a gerund or an infinitive? As a native speaker of English, the gerund version of this sentence sounds better:  infinitive:     When used together in chains,   extension methods are an unprecedented   tool to produce extremely concise   code.   gerund:     When used together in chains,   extension methods are an unprecedented   tool for producing extremely concise   code.   But how can I explain to someone learning English how to decide in situations like these whether to use the infinitive or the gerund? Prove that $d(n)\leq 2\sqrt{n}$ In Waclaw Sierpinski's book Elementary Theory of Numbers on page 168 there is the following exercise:  "Exercises. 1. Prove that for natural numbers $n$ we have $d(n) \leq 2\sqrt{n}$," where $d(n)$ is the number of divisors of n.  As a hint right below is given: "The proof follows from the fact that of two complementary divisors of a natural number $n$ one is always not greater than $\sqrt{n}$.  I understand the hint but I don't know how it can be used to prove $d(n)\leq 2\sqrt{n}$.  Complementary divisors are pairs of divisors that when multiplied gives the number that is to be divided. For example the number $120$ has the complementary divisors: \begin{align*} &amp; 1, 120 \\ &amp; 2, 60 \\ &amp; 3, 40 \\ &amp; 4, 30 \\ &amp; 5, 24 \\ &amp; 6, 20 \\ &amp; 8, 15 \\ &amp; 10, 12 \\ \end{align*} How do you prove that $d(n) \leq 2\sqrt{n}$? I was rewatching the Breaking Bad episode S04E08 (Hermanos) and I didn't quite understand why exactly Don Eladio killed Gus's partner, but he let Gus live. He says:     The only reason you're alive and he's not, is because I know who you are.   But I still have yet to fully understand. Probability that a k digit number does not contain certain digits JavaScript post request like a form submit Show that the boundary of a set equals the boundary of its complement $\newcommand{\bdy}{\operatorname{bdy}}$  I'm trying to show that $\bdy(A) = \bdy(A^c)$.  I know that $\bdy(A) = \operatorname{closure} A \setminus \operatorname{int}(A) = (\operatorname{int}(A^c))^c \setminus \operatorname{int}(A)$, but I don't know where to go from there.  Any help or hints would be very much appreciated. Shooting many bullets toward the mouse position I try to shoot a bullet toward the mouse position by this code.  float deltaX = mousePosition.x - (aircraft.getPosition().x + aircraft.getLocalBounds().width / 2); float deltaY = mousePosition.y - (aircraft.getPosition().y + aircraft.getLocalBounds().height / 2); float angleRadian = (float)(std::atan2(deltaY, deltaX)); float angleDegree = (float)(angleRadian * 180 / PI);   It works fine with one bullet but when I add another one bullet to shoot together I use this code to specify start shooting point of each bullets.  sf::Vector2f offset1(aircraft.getPosition()); offset1.x += -10;//start shooting point first bullet.  sf::Vector2f offset2(aircraft.getPosition()); offset2.x += 10;//start shooting point second bullet.   this is a picture of this problem.   When I rotate aircraft to picture 2 the bullets are not the same as the first picture.  How can I solve this problem? I am indian citizen on H1b visa in US. I am planning to visit France in Oct 2014. Can I apply for Schengen visa now about 3/4 months in advance. Are there any restrictions that on early you can apply for Schengen visa. If $\sum_{n_0}^{\infty} a_n$ diverges prove that $\sum_{n_0}^{\infty} \frac{a_n}{a_1+a_2+...+a_n} = +\infty $ I've tried to use the limit test: $\lim_{n \rightarrow \infty} \frac{a_n}{b_n} = C$ in the series of $a_n$ and $\frac{a_n}{a_1+a_2+...+a_n}$ but it was inconclusive.  The question does not especify the sign of $a_n$ but proving it for positives would already help.  I think the sign can change as long as the partial sums never get to be zero. Like if the series has only negative numbers the result seems to stil hold. Does $\mathbb R^2$ remain connected when countably many points are removed? Does it remain path connected?  This is not homework but is in response to working several problems where countable or uncountable many points are removed and the pattern always holds.  Thank you. Fixed background image with ios7 Splitting all lines in layer at vertices using QGIS If $f(xy)=f(x)f(y)$ then show that $f(x) = x^t$ for some t How to install squid-deb-proxy-client via preseed/early_command Using Lucid, installing from the Lucid mini.iso.  Both AMD64.  In the following I've tried as \, all of apt-get, apt-install, anna-install, dpkg:  d-i preseed/early_command string &lt;cmd+opt&gt; squid-deb-proxy-client   I've also tried:   d-i preseed/early_command string /usr/bin/wget \     -O squid-deb-proxy-client_0.3.1_all.deb \     http://ubuntu.media.mit.edu/ubuntu//pool/universe/s/squid-deb-proxy/squid-deb-proxy-client_0.3.1_all.deb &amp;&amp; dpkg -i squid-deb-proxy-client_0.3.1_all.deb   Is this possible, and if nor what is the earliest point one can get a installation to use the squid-deb-proxy server? Orphaned tag wiki edits have broken activity entries some \newcommand instructions not working