quadtard wrote:
I still dont understand why it seems the i7 and i5 processers seem to have shitty ghz while ancient models i see at the office have almost double it.
For the longest time Intel's marketing told the world "LOL GHZ MEANS FASTER!!!111" while AMD decided to be more practical about actual processor performance and came up with "performance rating."*
Basically, gigahertz is really "cycles/operations per second" or how many things per second the processor can do. 2.8 ghz means the processor can do 2,800,000,000 things every second. The problem is, that doesn't tell you what sorts of things it's doing in that time.
As a very basic example, let's say a older Pentium 4 processor at 2.0ghz is limited to simple "2+2" type arithmetic for each of it's operations. It can do 2+2 two billion times in one second.
An older AMD Athlon 2000+* has a clock speed of 1.6ghz. It's technically "slower" in that it can't do as many operations in one second as the 2.0ghz Pentium 4. However, it's capable of doing slightly more complex math with each cycle/operation. It can do something like "(2+2)*2" 1.6 billion times in one second. Because it's doing more work in each cycle, it can crunch data more efficiently than the "faster" 2.0ghz Pentium 4.
Intel realized this as they released the 3.8ghz Pentium 4, and it was getting smoked by Athlon 64s clocked 1ghz slower. So they essentially said fuck the Pentium 4 architecture, started reworking the Pentium 3 line, added new instructions, bumped the clock speed a bit, and came up with the Pentium M which evolved into the Core series (Core, Core Duo, Core 2, Core 2 Duo, Core 2 Quad, and eventually the i series). Since then Intel hasn't directly marketed any newer processors as "X.X ghz" but with model numbers, like Q9950, E8400, i7-920, etc.
That's why they're now selling processors half the "speed" as a few years ago, yet they're really almost twice as fast. They've recently started hitting a cap in how fast they can push clock speeds with all those extra instructions, so their solution now is to add more processing cores to each chip. Hence the Dual/Quad/Six/Eight core chips. It'll be some time before the majority of software can really take advantage of multi core, but it's getting there.
*AMD's performance rating system was based on the speed of a 1ghz Athlon Thunderbird processor. They would benchmark newer processors and compare the results to those of a 1ghz Thunderbird. The Athlon 2000+ (at 1.6 ghz) was roughly twice as fast as the 1ghz t-bird, so 2x1000mhz = 2000 effective mhz = 2000+ performance rating.
