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Hello Daniel,
thanks for the great overview. your post will go in my "keeper" file.
Best regards,
Jim Johnson mailto:jejohn@xxxxxxxxxxx
--
Monday, July 22, 2002, 12:41:37 AM, you wrote:
DM> The top speed of the Intel Celeron and AMD Duron processors (CPU's) is 1.3
DM> GHz. The top speed of the Intel Pentium 4 and the AMD Athlon are 2.53 GHz and
DM> =2.2 GHz, respectively. Most P4's and Athlons sold today are faster than 1.3
DM> GHz. However, suppose you have 4 systems: 1.3 GHz Celeron, Duron, P4, and
DM> Athlon. The difference is with the memory inside the CPU called the cache, the
DM> type of memory the system uses, and the additional multimedia commands the CPU
DM> can handle.
DM> The cache is expensive to build into the CPU because it makes the physical die
DM> size larger. The larger the cache, the less the CPU must reach into main
DM> memory which is farther away and slower. The Celeron and the Duron are the
DM> budget cpu's. They have a smaller cache. The P4 and the Athlon have a larger
DM> cache. Some specialized Pentiums, called Xeons, have 1 MB of cache and cost
DM> over $3,000. If you want cache sizes, go here:
DM> http://www.geek.com/procspec/procspec.htm
DM> Without opening the box, it can sometimes be difficult to figure out what type
DM> of main memory sticks a system uses. It can be either, by order of speed and
DM> expense, SDRAM, DDR-RAM, or RDRAM. AMD CPU's only use SDRAM and DDR-RAM.
DM> Until this year, most P4 systems only had RDRAM installed. Intel decided to
DM> reduce their RDRAM commitment and support SDRAM and DDR-RAM. SDRAM is oldest
DM> and slowest standard. A system with SDRAM, no matter how fast the CPU, would
DM> be slower when creating large ZIP files, multimedia files, handling video,
DM> etc... RDRAM is the most expensive and the fastest. However, because the
DM> Athlon is so enhanced, at the same speed with DDR-RAM it is usually faster than
DM> a P4 with RDRAM.
DM> Beginning with the Pentium in 1995-6, CPU makers started including extra
DM> multimedia command sets. These commands are additional features and are there
DM> for programmers to exploit. I don't remember them all or all the details. The
DM> Celeron can use MMX, SSE, SSE2; Duron MMX, 3DNow!; Pentium 4 MMX, SSE, SSE2;
DM> Athlon Thunderbird MMX, 3DNow!, Enhanced 3DNow!; and Athlon XP & ThoroughBred
DM> MMX, 3DNow!, Enhanced 3DNow!, SSE. These command sets are used to accelerate
DM> multimedia functions in games, playing DVD's, possibly music, etc... Not all
DM> games and apps exploit all advantages in a CPU. Very few applications use SSE2
DM> commands or Enhanced 3DNow!. Even so, games and applications have no problems
DM> running on all 4 CPU's.
DM> Because this is such a complex subject, it is difficult to be brief. This is
DM> about as simple as you can get without throwing out details. Below is
DM> additional material concerning a new CPU.
DM> Personally, I prefer the AMD line of CPU's. Late this year, the new AMD K8
DM> (Opteron and ClawHammer) arrives. The K8 will have 64-bit capability and, more
DM> importantly, a built-in memory controller. Unlike the new Intel Itanium, the
DM> K8 has native 32-bit support which means it should be just as fast as AMD's
DM> current Athlon CPU's with standard apps. Because the K8's memory controller is
DM> built-in, it should be much faster when moving large amounts of data. Unlike
DM> all previous AMD CPU's which have their memory controller on the motherboard,
DM> the K8's onboard memory controller should fully exploit any DDR-RAM used with
DM> it. The Abit KG7-RAID motherboard I purchased in September uses the AMD 760
DM> chipset which has a slow memory controller. While subtle, the speed
DM> limitations are noticeable while moving large amounts of data.
DM> Daniel.
DM> Jim wrote:
>> No doubt this is obvious to many but not to me:-
>>
>> Would someone briefly explain in laymans terms why it matters which type of
>> processor (pentium/celeron/athlon) is in use if their quoted speeds are the
>> same.
>>
>> TIA
>>
>> Jim
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