Feeds

* Posts by Dominic Sweetman

6 posts • joined 17 Jan 2008

Climate was HOTTER in Roman, medieval times than now: Study

Dominic Sweetman

CO2 levels are 60% higher than in the late 18thC, and are still rising fast. There's a very simple mechanism which causes it to raise global temperature. Climate is far more complicated than we can understand: perhaps there is some not-yet-known feedback mechanism which means we won't get much warmer. But given the least worst science available, most likely it will make it quite a lot warmer rather fast, which is likely to be difficult for our grandchildren. If we had another planet or two for us to move to if it turns out badly, that might be a reasonable chance to take.

But we haven't got another planet.

We know how to stop adding CO2. It wouldn't even cost that much. We won't do it. That's amazingly stupid, and we don't like admitting to stupidity, so we grasp at straws. Or scandinavian tree-rings, of course.

0
1

Superfast-charging batteries? Whoa there, MIT

Dominic Sweetman

Battery charging at home

A correspondent does the maths implicit in your article... Yes, charging my phone's 1Ah battery in 9 seconds would require a current of 400A. But that's only at 3.7V, so the amount of power involved is about 1.5kW, half of an electric kettle and well within the maximum of a regular 13A/240V plug. Surprisingly high currents are provided in domestic environments -- your PC power supply feeds its CPU chip with over 90A of current. Nine seconds: hardly. Three minutes? there's no obvious power supply reason why not.

0
0

'Jisus' Eee-alike sub-notebook to use Chinese Atom-smasher

Dominic Sweetman

Why choose

A MIPS CPU is a lot simpler than an x86, which means less transistors in the CPU's heart. But almost all the transistors on a CPU chip are cache and interface anyway, so it won't ever make up for the huge economies of scale in the x86 clone market. But while you can't buy a chinese x86 yet (for legal and political reasons, you can get the chinese MIPS.

It will never run Vista, so you won't even be tempted. That's got to be a plus, too...

0
0
Dominic Sweetman

Why choose

A MIPS instruction set (RISC) CPU is a lot simpler than an x86, which means less transistors in the CPU's heart. But almost all the transistors on a CPU chip are cache and interface anyway, so it won't ever make up for the huge economies of scale in the x86 clone market. But while you can't buy a chinese x86 yet (for legal and political reasons, you can get the chinese RISC.

It will never run Vista, so you won't even be tempted. That's got to be a plus, too...

0
0

Intel to tell all about roaring 96GB/s QuickPath interconnect

Dominic Sweetman

CPUs need low latency, not high bandwidth

Fast CPUs need their interconnect to provide the data they need, fast (they're probably stalled waiting for that data). While too-low bandwidth gets in the way, the critical factor is more often the time until the first datum you asked for arrives ("latency"). Prof Roger Needham used to say that "bandwidth can be made by man, but God makes latency".

Nobody ever quotes the minimum latency which is practically achievable with their interconnect, because as the interconnects get more amazing, it generally gets worse... So this bandwidth claim, like almost all other such, is irrelevant.

BTW, optical enthusiasts should probably try to convince us that four electric/optical transitions in their favourite path doesn't add delay.

0
0

Hasbro fires off legal letters over Scrabulous

Dominic Sweetman

Copyright on scrabble

If it was just a trademark, "Scrabulous" could just change its name (assuming it's plausible that it confuses -- it seems pretty distinct to me).

Any patent (there was a 1956 US patent relevant to the scrabble board) expired long ago.

So what's left is copyright. The inventor of scrabble died only in 1993 and -- in the UK at any rate -- I believe this is treated like an artistic work, so that's 70 years after the death of the author. But apparently courts are inclined to limit the copyright to fairly precise reproduction of artwork... this could run on.

0
0