January 23, 2009

ThinkPad T400

As I was looking for a laptop with the right balance of performance, mobility, and price that works best for my needs, I narrowed down my search to a display size of 13.3" or 14.1", +256MB graphics adaptor, and a low/medium voltage Intel Core 2 Duo with +1066 MT/s, +6MB L2-cache, and +2.5GHz clock rate.

The list of Intel Core 2 CPUs

Reliability of a manufacturer plays an important in my decision and I favour Lenovo ThinkPads and Dell XPS's (Mind you, Apple products are fashionable but expensive. They never win the performance/price game, esp. when I play the game. If you own one, don't get pissed or anything. Probably you have maximized fashion/performance, which is cool just not my game).

So, I narrowed down to Lenovo ThinkPad T400, Dell XPS M1330, and the new Dell Studio XPS 13. The highest performance CPU under M1330's hood is T8100 (2.1GHz; 800MT/s; 3MB L2-cache; 35W; Jan. 2008) with a 128MB NVIDIA® GeForce™ 8400M GS graphics card. I think I remember higher performance CPUs there; perhaps Dell has shifted the performance focus to Studio XPS product line. The Studio XPS comes with P8400 and NVIDIA GeForce 9400M G. The CPU can be upgraded to the newer P9500 (2.53GHz; 1066MT/s; 6MB L2-cache; 25W; Jul. 2008). With some other desirable configurations and a 3 year complete care service, the price got to almost $2100 CAD before taxes (that's with a $170 online purchase discount). The Lenovo T400 that won my heart configured to have a T9400 CPU (2.53GHz; 6MB L2-cache; 1066 MT/s; 35W; Jul. 2008) and ATI Radeon 3470 256MB graphics card. With a 3 year easy serve + accidental damage protection (equivalent to Dell's complete care), the final price got to only $1836 CAD (that's with a 48 hour sale coupon which expired Jan 22). With taxes and adding an extra AC adaptor the total order is still under $2000, which is way cool to be true.

Searching for the right machine, I came across many PC/Graphics benchmarking tools and performance measures to help me compare performances. The most popular benchmarks are the 3DMark series by FutureMark Corp. The benchmark provides a normalized mean for the overall performance of the GPU/CPU. There are three very popular products in their line: PCMark Vantage, PCMark05, and 3DMark06. Their 3DMark06 is very popular among gamers and the score is used to measure and compare the 3D performance. Although I was not shopping for a gaming laptop, I was just curious to see how my desired machine would score.

According to a thread reply on notebookreview, ThinkPad T400's scores for 2.80GHz Intel T9600 and ATI Radeon 3470 256MB GDDR3 with 12800x800 resolution are
6589 in PCMark05
2575 in 3DMark06
4374 in PCMark Vantage

Do you have the PC Mark scores for a Dell Studio XPS 13?


How highspeed is your high-speed?

Have you ever wondered how fast your Internet really works? There's an answer to that, beyond the claims of your ISP. Alternatively, you can tune in to and get your hostname, IP address, and some other info, then click on Test Internet Speed.

My current bandwidth meter reads 1.19 Mbps, "which means you can download at 152.38 KB/sec. from our server." What are your numbers?


January 20, 2009

Coffee Chat: Robot Learning

School life is more interesting than ever. With no courses or TA duties, I have full luxury to learn new trends in robot learning. Amir massoud gave a talk on his ICRA 2009 paper in our group meeting today. Afterwards, we headed to SUB (the Student Union's Building @ Univ. of Alberta) for a coffee and a nice chat about robot learning, visual servoing, parametric vs. non-parametric, and model-based vs. model-free reinforcement learning.

In addition to Amir massoud's reading list on estimation and control of robotic systems, I added the following papers to my to-read list:
  • Sethu Vijayakumar, Aaron D'Souza and Stefan Schaal, Incremental Online Learning in High Dimensions, Neural Computation, vol. 17, no. 12, pp. 2602-2634 (2005). [pdf] [More detailed version of the paper Tech Report EDI-INF-RR-0284 of UEDIN]
  • Manuel Lopes and Bruno Damas, A Learning Framework for Generic Sensory-Motor Maps, Proc. IEEE/RSJ Intl. Conf. on Intelligent Robotics and Systems, pp. 1533-1538, San Diego, CA, USA, Oct 29 - Nov 2, 2007. [pdf]
Also of general interest to robot learning researchers are the publications of Stefan Schaal, Michael Mistry, and Jan Peters. Also check the rest of Vijayakumar's publications and his research group page at University of Edinburgh. The future of robot learning is very exciting.

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