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Comment Re:Why use PS3s? (Score 5, Informative) 211

since CUDA is roughly C

Not quite. CUDA looks a lot like C in that it has C-family syntax but the biggest limitation it has is that there is no application stack - which means no recursion. CUDA also lacks the idea of a pointer, although you can bypass this by doing number to address translation (as in, the number 78 means look up tex2D(tex, 0.7, 0.8)). The GPU also has other shortcomings, in that most architectures like to have all their shaders running the same instruction at the same time. For this code

if (pixel.r < pixel.g){
//do stuff A
}else if (pixel.g < pixel.b){
//do stuff B
//do stuff C

The GPU will slow down a ton if the pixel color causes different pixels to branch in different directions. Basically, the three sets of shaders following different branches of that code will be inactive 2/3 of the time.

In the Cell, you really do just program in C with a number of extensions added onto it like the SPE SIMD intrinsics and the DMA transfer commands (check it out). The Cell really is 9 (10 logical) processors all working together in a single chip (except in PS3, where there are only 7 working SPEs). Furthermore, your 8 SPEs can be running completely different programs -- they're just little processors. Granted, you have to be smart when you program them to deal with race conditions and all the other crap you have to deal with for multithreaded programming. The Cell takes about 14 times longer to calculate a double precision floating point than a single (and there aren't SPE commands to do four at once like you can with singles).

So which is more powerful? It really depends what you're doing. If your task is ridiculously parallellizable and doesn't require the use of recursion, pointers or multiple branches, the GPU is most likely your best bet. If your program falls into any of those categories, use a Cell.

PlayStation (Games)

Submission + - Accellerated X drivers coming for PS3 Linux (ps2dev.org)

t0qer writes: Over at the PS2dev forums a hacker named Ironpeter has successfully managed to bypass the PS3's Hypervisor to gain direct access to it's Nvidia RSX GPU.

This is s first step and far from a complete working driver, but it seems as word of this spreads, more people are helping with the effort to hunt down the Hypervisors Fifo/Push buffer. It won't be long before we're playing tux racer on the PS3 in it's full OpenGL glory.


Submission + - Scanning railroad tracks in 3D (controleng.com)

An anonymous reader writes: Control Engineering has an article about how the railroad companies are using high-speed 3D scanning at 30 mph to detect defects in railroad track. Up until now, amazingly, people have been walking the track to judge the condition of it.

Submission + - How Gateway tech support tortured an editor

An anonymous reader writes: A tech editor tells his story of being to the Gateway of Hell, that is, dealing with Gateway's tech support for the past year regarding a home desktop computer. He relates one anecdote as such: "If you call us up because you forgot your password, we'd have you do a system restore," the support person told me. I wasn't sure if he was joking. He said the company's "Our Answers by Gateway" people would figure out a less extreme way to solve a problem, but you need to pay extra for their advice. http://www.networkworld.com/news/2007/091707-gateway-complaint.html

Trent Reznor Says "Steal My Music" 637

THX-1138 writes "A few months ago, Trent Reznor (frontman of the band Nine Inch Nails), was in Australia doing an interview when he commented on the outrageous prices of CDs there. Apparently now his label, Universal Media Group is angry at him for having said that. During a concert last night, he told fans, '...Has anyone seen the price come down? Okay, well, you know what that means — STEAL IT. Steal away. Steal and steal and steal some more and give it to all your friends and keep on stealin'. Because one way or another these mother****ers will get it through their head that they're ripping people off and that's not right.'"

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