10 November 2012

Achievement Unlocked: GPU Insanity

You are looking at two gorgeous eVGA GTX 460 2Wins, which are eVGA's attempt at the dual GPU thing. I nearly had a shortage of 8-pin connectors (there's only two on this power supply), but was solved by using a dual 6-pin to 8-pin adapter (and then I almost ran out of 6-pin connectors -- go figure). My test cuda code verifies that I indeed have four GPUs:

shewu@hamburger ~/Dropbox/Projects/cuda
 % ./getgpu 
This computer has 4 GPUs
CUDA device #0
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz
CUDA device #1
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz
CUDA device #2
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz
CUDA device #3
Name: GeForce GTX 460
Total memory: 1024MiB
Clock rate: 1401MHz

If you're interested in the code, here it is:

#include <iostream>
#include <cuda.h>

using namespace std;

void printDeviceProp(cudaDeviceProp& devProp_)
        cout << "Name: " << devProp_.name << "\n";
        cout << "Total memory: " << (devProp_.totalGlobalMem/(1024*1024)+1) << "MiB\n";
        cout << "Clock rate: " << devProp_.clockRate/1000 << "MHz\n";

int main()
        int devCount;
        cout << "This computer has " << devCount << " GPUs\n";

        for (int i = 0; i < devCount; ++i)
                cout << "CUDA device #" << i << "\n";
                cudaDeviceProp devProp;
                cudaGetDeviceProperties(&devProp, i);

        return 0;
Sad to say that I still can't tell Bayley to eat my dust just yet.

09 November 2012

Steering: Conquered

I finally fixed the steering on KawaiiKart, which meant securing one of the two remaining degrees of freedom so that the steering column won't wobble while trying to steer. Here's the updated CAD:

I did the entire CAD on my MacBook Pro Core Duo (yes, one of the first MacBook Pros!) 2.0GHz with 2GiB RAM and a now wimpy ATI Mobility X1600 driving a custom 1920x1200 panel. I'm very impressed by how old hardware works. Then again a 100-part assembly isn't very much at all.

In other news, I got a $500 grant from Techfair to partially fund building Kawaii! I estimate the build will run upwards of $1.2k, since waterjet parts are expensive (~$400), but the journey and the end product will be well worth it. Stay tuned!

07 November 2012

iPad mini Impressions

I went to the Apple Store in Legacy Place the day after launch day to check out the newest tablet in town. The same weekend (actually on launch day), I received my iPad 4, an early Christmas present from the parents.

Of course, iPad mini was sitting on a table near the entrance. I picked up the unit closest to me and started playing around with it. Immediately I noticed how light it was; its thinness came second. Its svelte proportions begged me to fit it in my pocket. Surprisingly, it did! (At least in my ski jacket pocket. It went only halfway into my pants pocket. Clearly I should get real cargo pants.)

I then investigated its usability. Upon waking the device, I noticed the blurriness of the clock and app names. Icons were smaller, but still plenty touchable. I then pulled up some scientific papers, but the unfortunate combinations of large margins and smaller and blurrier text heavily outweighed the size and weight of the device. Although I was decided on the iPad 4 at this point, I did my handwriting and typing tests for sake of completeness: I opened up the Paper app and started writing. While a 4:3 ratio is optimal for these smaller devices, 7.9" diagonal does not provide sufficient surface area for writing notes without constantly flipping pages. Yes, I do handwrite my notes on iPad with a stylus, and it works remarkably well. The typing test went surprisingly well; while the keys are considerably more cramped than those of the iPad 4, I was able to type surprisingly quickly (~50wpm).

My impression of iPad 4 is more positive. The retina display is absolutely gorgeous. Also noticeable is the increased weight from iPad 2; while it is heavier, it will be lying on a flat surface most of the time for writing notes. The device does get warm under heavy use (games), in particular, like the iPad 3, the bottom left gets noticeably warm. Perhaps the best change is the speakers (yes, there are two speakers behind the grill); they are significantly louder, maybe on par with those in MacBooks.

The iPod touch is pretty nice, but the iPad nano was pretty bleh. What in the world was Jony Ive thinking?! I'm slightly convinced that it was designed by the marketing team. Ha.

That's all for now; I'll report back if I notice more worthwhile tidbits.