Prescott heat Problems to get worst?

Sinceramente não me estou a ver a "enterrar" dinheiro num produto que poderá não corresponder às minhas espectativas, para isso prefiro aguentar-me com o A64, que está-se a portar muito bem, e quando sairem os outros Prescott, com o novo socket, então ai apostar...


(estou a falar mas muito provavelmente não resistirei e compro um! :P)
 
Cuidado que esse é um ES.

Essa preview já andou aqui no forum. É principalmente daí que vem a ideia do "forno", seja ela verdadeira ou não.
 
procura uma decente review sobre fontes de alimentação.... na maior parte delas vais ler algo do genero:
"...it's better to have higher power rails than lower to provide better voltage to components..."

exemplo

por 2 power rails, entendo por exemplo, 2 fontes :004:
um duplo power rail so me faz sentido se usar 2 fontes... nao vejo outro significado...
 
Prescott: let us talk performance

Our previous newspost about Prescott's power consumption generated some brilliant and enlighting posts. The Ace's crew likes to thank you all for improving the quality of our messageboard to an excellent level again :).

Now that the Prescott launch is getting closer and we have a pretty good idea what the architectural improvements are, we can make some decent predictions. To refresh your memory let me reiterate a post that I published in September 2003. Prescott is basically a Northwood Pentium 4 with the following improvements:


bigger D-L1 cache (16 KB instead of 8 KB) & L2-cache (1 MB instead of 512 KB) .. No comments necessary
4x Improved Clock Distribution (compared to Northwood) for better Frequency Scaling
Automated design of the functional blocks for better clockscaling
Improved Imul latency : Northwood/Willamette do their integer multiplications on the FPU, and the big latency is due routing the data between integer and FP datapaths. Prescott has a dedicated integer multiplier. (Thanks goes to Heikki Kultala).
Prescott New Instructions (SSE-3), which will not improve performance at the launch (needs optimized software).
Additional WC Buffers. Instead of sending small pieces of data to the AGP videocard, these pieces of data are stored together in buffers, and send through in one big burst. This helps to preserve FSB bandwidth as the bandwidth of the FSB is more efficiently used (less overhead from one big burst than from many small ones)
Improved Pre-Fetcher Branch Predictor. I did not get much info on this but it seems that the buffers have been made bigger so the branch predictor will be able to cope better with more then one thread.
Improved Hyperthreading: two new instructions: Monitor and Wait, which will only improve performance on recompiled software.
we can add two more, one being a fact and another being a rumor:

longer pipeline (fact)
Higher L2-cache latency ? (rumor)

Now if you just look at the first group you would assume Prescott is a super Pentium 4: better clock scalability and more IPC. However, SSE-3 software will not exist at the launch of Prescott, additional WC buffers are not going to make much difference and the small difference gets even smaller because the 800 MHz FSB has access to a very decent amount of bandwidth. The improved imul latency could help, but the real bottleneck of integer code lies in branches. Not even a 6.8 GHz ALU is going to help there. The impact of the 16 KB L1 should not be overestimated as 16 KB might have seemed much back in the days of the 486DX4 but critical loops of the software of today requires much more.

So we are left with fast twice as big L2-cache and L1-cache, and a slightly improved branch predictor of which the effect is probably totally negated by the higher branch misprediction penalty. This means that some software will not run - clock for clock - faster on the Prescott than on the Northwood P4. So besides SSE-3 optimized software, and software that benefits from hyperthreading, a 3.4 GHz Prescott will -IMHO- perform like a Northwood 3.4 GHz.

Basically, I expect that most games will run on it like on a 3.4 Ghz Northwood, In fact, many games are already using the CPU more and more for AI (Battlefield 1942 uses up to 25% of the CPU's clockcycles). The software where Intel is already doing well such as Lightwave, Cinema4d and 3DSMax, will show the Prescott being faster clock for clock than Northwood. With two or more threads, the extra L2-cache space will be put to good use. Intel's main objective with Prescott is getting higher clockspeeds out of Netburst without lowering the IPC.

More data in February...
Clicar para expandir...

http://www.aceshardware.com/#75000461

Analise interessante.....
A parte do "longer pipeline (fact)" já se sabia antes? Acho que é a 1ª vez que vejo esta informação em relação ao Prescott.
 
Espero não tar a dizer asneira, mas cpm um pipeline mais longo o processador não fica menos eficiente? Tipo, não precisa de maior velocidade para realizar o mesmo trabalho?
 
imagina a cena, tens uma pipeline bue grande, cheia ate as costuras.
as tantas, chega-te um branch (se "isto", continua, senao vai pra outro sitio), e primeiro vais ver se ele se verifica... se verificar, tudo bem, senao tem de mandar pro lixo tudo o q vinha pra tras e começar a meter as instruções do tal sitio para onde a branch o mandou.
Axo q isto eh so um dos aspectos. Mais calor gerado, sera outro...

mas por outro lado, tb nao percebo mt disto :P
 
Nemesis,

excelente análise a qual só poderia ter vindo do Aceshardware.
Praticamente o único site que sabe o que diz.

Já se sabia que o Prescott iria ter um pipeline mais longo.
É natural que isso aconteça à medida que a frequência vai
aumentando. Tb aconteceu no A32->A64.

É óbvio que é chato quando há coisas como as que foram
referidas no post anterior mas bons programadores
podem conceber código optimizado em que isso pouco acontece
ou tem pouco impacto. Os compiladores tb podem dar uma
ajuda.
 
Originally posted by iJFerreira

É óbvio que é chato quando há coisas como as que foram
referidas no post anterior mas bons programadores
podem conceber código optimizado em que isso pouco acontece
ou tem pouco impacto. Os compiladores tb podem dar uma
ajuda.
Clicar para expandir...

e eu tou-me a lembrar de umas aplicações mais ou menos comuns em que os branches são o prato do dia...
 
Mais uma acha

Intel Prescott edges close to 100 watts


WITH THE launch of Prescott just over a week away, the power FUD continues to swirl, and there appears to be no sign of it letting up.
Rather than bitch and moan like we usually do, we decided to go out and measure the power consumption.

Before you delete your bookmarks, we will get back to bitching and moaning soon, it's just that we ran out of booze, and in a moment of clarity, decided to do something useful for a change.

So, the numbers we got for a Prescott 3.4 are 95w, perilously close to the 100w ceiling for the chips. Going a little further, if you push this chip to the limit, an OC’d Prescott at 4.0GHz consumes 135w.

Before you all write, let me answer the two questions you will all ask.

The 4.0GHz model isn’t a fair test, and the power consumption will undoubtedly come down before "official" release. The next thing will be test configuration, and the simple answer here is "no".

Time to go drink, breakfast awaits. µ
 
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