It is true that the G4 is faster than the Pentium III on many task . For example , if you black market theSETI@home screensaver(which uses lots offloating - compass point calculationsto perform signal processing surgical operation onradio scope data ) , a G4 running at 500 megahertz ( MHz ) will raise a result determine in about half the time of a Pentium III running at 700 MHz . This is a remarkable difference in processing capability .
When create amicroprocessor , the designer catch to make millions of decisions . A basic limit in the aim is the identification number of transistors that will conform to on a chip , so the designer is try out to make decisions that hold the in effect execution from those junction transistor . The designer may also have to worry about backward compatibility with older instruction sets and looming liberation dates .
For example , the Intel 8080 mainframe took something like 80 clock cycles to multiply two 8 - bit numbers . It took so long because the turn of transistors was seriously limited at the time the 8080 was release . Today ’s processors can often multiply two brace of 32 - mo numbers in a individual clock rhythm . The difference between then and now is thenumber of transistors– a greater number of transistors allows more to hap in a undivided clock cycle .
If you look atMotorola ’s support , it says that theG4 processorfeatures :
These execution unit bung off of a128 - bit internal bus . The feature film that gives the G4 most of its speed in SETI@home processing is thedouble - precision floating - point unit . The G4 can nail one double - precision calculation every clock cycle , while the Pentium III can not .
The G4 also have an interestingvector processing social unit . Applications must be peculiarly rag to take vantage of the vector processor , which allow them to perform certain mathematical operations very quickly . A transmitter central processing unit execute the same operation on multiple pieces of datum at the same time . In the G4 , up to eight simultaneous surgical operation can execute in a single clock cycle in the transmitter unit . This sort of processing power is what makes the G4 so tight when work with math - intensive practical software likePhotoshopthat have been coded to take advantage of vector processing . The Pentium III features a transmitter processing capacity as well , but it is not as powerful .
