So what else is new? Well, I’m sure you’ve heard of SSE (Streaming SIMD Extensions) and SSE2, a collection of specialised instructions designed, in Intel’s words to “help accelerate a broad range of applications, including video, speech, and image, photo processing, encryption, financial, engineering and scientific applications.” Well, Prescott features 13 new ones, one for floating point to integer conversions, five for complex arithmetic, one for video encoding, four for SIMD-FP using AOS (Array-of-Structures) format and two for thread synchronisation. Not surprisingly Intel has christened this SSE3.
In true Intel fashion there is already support both available and planned to take advantage of SSE3. Current titles include MainConcept (MPEG 2/4), xMPEG, Ligos (MPEG 2/4), Real (RV9) and On2 (VP5/VP6) with more planned for this year including Pegasys TMPGEnc 3.0, DVD Author, Adobe Premier (to use MainConcept codec), Pinnacle (MPEG Encoder & use DivX Codec), Sony DVD Source Creator ( bundling Pegasis TMPEG Encoder), Ulead (MediaStudio & Video Studio) and Intervideo, Pinnacle, Showshifter, Snapstream (All using DivX Codec)
Last but not least there are several claimed improvements to Prescott’s thermal protection capabilities and enhancements to the existing NetBurst and HT (Hyper Threading) technology along with a full 1MB of on-die Level 2 cache, an increased 16KB of Level 2 data cache and a 12k uops instruction cache. Also in the design brief comes speculative pre-computation that uses idle time to compute calculations it predicts may be needed next or soon.
Hyper Threading is a technology that Intel is very proud of and if it’s a term that doesn’t mean a lot to you let me quickly explain the principle. It doesn’t take too much technical knowledge to realise that having two CPUs beavering away on your behalf will be more productive than having a single CPU, and in essence that’s what Hyper Threading does. But rather than you needing to buy two separate CPUs, Hyper Threading technology allows your single CPU to divide itself in half and work on two things simultaneously.
Now you may be thinking that most processor can do that, but in actual fact when you’re working on two things at once using a non-HT processor it’s actually dividing its time back and forth between those two tasks rather than actually working on both at the same time.
Despite how it might seem, Hyper Threading isn’t twice as fast as non Hyper Threaded processing, in fact it’s not even close, but it does help provide a bit of a boost provided your software has been written to take advantage of it. Think of it kind of like employing a guy who can work with both hands at the same time slowly rather than employing two guys who would be significantly quicker.