January 9, 1999
You are deciding to either upgrade your existing computer, build your
own computer or just buy a system. You have been looking around and hear about new
hardware and it seems confusing. The most important issue if you are going to upgrade,
build or buy is getting future return for the money you are investing.
Investing money in a computer now with hopes that it will be still
state-of-the-art four years from now is not possible. Four years ago, I was building
486DX-120 systems on VLB motherboards. A 2mg VLB video card was considered big and fast at
that time, 16megs of ram made the system run ‘fast’ and a 650meg hard drive had
room to spare. That was four years ago and today we know that such systems were
out-of-date within a year.
So, how do you know where the best investment is for the future? You
don’t know… I don’t know. We can only guess and make wise decisions based
on current needs without spending too much money.
I am going to give you a few guidelines for building, upgrading or
buying in today’s market. Mostly this will be common sense.
Currently there are several chipsets, (the structure of the
motherboard), that are very popular. The TX, LX, VIA & ALi chipsets are very
economical. The TX chipset supports the socket7 chips, basically Pentium chips and the new
fast AMD and Cyrix chips. The LX chipset can be found on low-end PentiumII motherboards.
These will allow you a faster computer that meets minimum standards. The
ALi & VIA chipsets are designed for Super Socket7 motherboards and use with the 100mhz
AMD/Cyrix Pentium style CPUs. These are not the wave of the future, they are
standards used as stop gaps for economical computers. I am a bit biased against this
approach of using faster CPUs in Socket7 motherboards, remembering the issues that occured
for people who hung on to the Socket3 motherboards, (486 motherboards), to forstall
upgrading to Pentiums three or four years ago.
The BX chipset is today’s current cutting edge for PentiumII
systems. Prices are falling rapidly on these motherboards and they can be purchased for as
little as $100. Always look for the latest technology and then find the best price. But,
after saying that, remember that the motherboard is the heart of any computer. Issues of
compatibility always derive from the motherboard as it supports your CPU, your ram, your
hard drive, video and audio cards… it is the base of your system. It is best to use a
name brand motherboard, one that will have upgrades for the Bios, (the underlying software
that allows the system to recognize your hardware), available in the future for hardware
improvements. The motherboard is never a very good place to save money, though many will
go with generic motherboards to have extra money for fancy video or audio cards. Then they
fight the motherboard to accept them.
I recommend a BX motherboard.
As I mentioned before, four years ago 16megs of ram was considered a
great deal of memory. Today 32megs is considered to be entry level, 64megs is average and
128megs optimal. I recommend going with at least 64megs and More if you can afford it.
All the new motherboards today support SDRAM or 168pin memory. Some
motherboards will still allow the use of the older 72pin simms, but that is not a good
reason to buy simms. Simm memory will only operate at a maximum speed of 50ns, (they are
available in 70, 60 & 50), while SDRAM starts at 10ns and is offered at 8ns. SDRAM
comes in both 66mhz and 100mhz speeds, (100mhz are often referred to as PC100 ram). Even
if you intend to build a system that only uses a CPU that runs at 66mhz, (333mhz CPUs and
lower run at 66mhz, while the faster chips run at 100mhz), the faster PC100 Ram memory is
only a minor increase in cost. It is a wise investment to buy the faster PC100 memory so
it will be effective when you decide to upgrade to faster CPUs in the future. PC100 ram
will run on a motherboard set at 66mhz for the slower CPUs and removes the need to upgrade
your memory when you upgrade to faster CPUs.
I recommend 128megs of PC100 SDRAM.
The CPU is the real speed of your computer, that is if you have the
motherboard and Ram memory to allow it run at the proper speed. Today AMD and Cyrix are
selling very fast CPUs that will run on ALi chipset motherboards using the Super socket7
slot on the board, (Pentium style CPU). We cannot recommend this option for a few reasons.
The ALi chipset is not compatible as of this writing with the TNT Riva high-speed video
cards, as we have recently discovered. This chipset is designed for one purpose and that
is to provide the 100mhz CPU speeds from older styled motherboards. It is a stop gap to
provide inexpensive CPUs and motherboards for OEM manufactures. These 350mhz – 400mhz
CPUs are fast, but have many compatibility issues springing from the motherboards that
support them and this needs to be addressed.
The future of computers is not with these low-end motherboards and CPUs.
They are a strong seller for the immediate market and have no future upgradability.
This brings us to the Intel PentiumII chips. Today there exist three
levels of the PentiumII CPUs. The Celeron chips, the classic PentiumII (also known as
Klamath) and the Xeon PentiumII CPU. The classic PentiumII CPU is the standard today in
Slot One CPUs. So, what is the difference? I will boil it down, maybe simplistically, but
in as general terms as I can.
What is the primary difference between Classic (also known as Klamath),
Celeron & Xeon CPUs? Although there are many minor differences, the main issue is L2
cache or Level2 cache. What is L2 cache and why is it important? L2 cache is a small
storage area for data moving through the CPU, (yes, that is over simplified), that allows
the CPU to more evenly move data in larger blocks. Without L2 cache CPUs tend to slow down
dramatically in performance, no matter the speed. The best way to demonstrate this is with
this little test of copying a floppy disk. If you turn off the L2 cache in your Bios and
copy a floppy disk, one disk to another, and then turn it back on, repeating this
job… you will see a dramatic difference in the time required. This is not the only
benefit of L2 cache, but a demonstration of it’s importance.
Classic PentiumII (also known as Klamath)
The original PentiumII CPU comes in two bus speeds, or speeds that the
data moves across the motherboard, 66mhz and 100mhz. The 350, 400 & 450 Pentium II
CPUs are all 100mhz chips, the PentiumII 333 – 233 CPUs are all 66mhz chips. All
these CPUs have 512k L2 cache.
The Celeron chips were produced as a low-end option to market against
the AMD & Cyrix chips. Initially these CPUs had zero L2 cache. The Celeron(a) series
CPUs were introduced with 128k of L2 cache. The one upside about the Celeron(a) chips is
the inherent ability to "overclock" the CPU. There is new anecdotal information
that the current versions of these CPUs have a lower tolerance to overclocking. Initially
the success rate was above 95%, but it now seems to have been lowered to around 65%. So,
beware of overclocking this chip.
The Celeron(a) 366 & 400mhz CPUs just introduced provide the speed
users are requiring, while still only offering 128k of L2 cache. Although I have no
experience with these CPUs, I understand that they are bus frequency and multiplier
locked, (overclocking will not be an option). Further, Intel has recently announced
that it will be producing the Celeron CPUs in Super Socket7 format, (the 370 pin
socket). Intel is obviously fearing their market share will be diminished by the
AMD/Cyrix CPUs. - More on this at Intel -
The Xeon chip is very expensive at this writing, 400% or more of the
classic PentiumII CPU. The major difference in the Xeon CPU is the Level2 or L2 cache on
the chip. Xeon offers 1mg or 1024k of cache, and even 2mgs of cache. The processor speeds
are not increased over the Celeron or classic chips, only a major increase of onboard L2
cache. This increase in L2 cache makes the CPU a greater performer in a Server environment
where vast amounts of data in large blocks stream through the chip. Most workstation or
home user systems will not experience any improvement of speed using these CPUs. Since the
demand for classic PentiumII CPUs for workstations and home user systems far out strips
Server usage of the Xeon chip, the volume production vs. sales has driven the price of the
Classic chip to a lower point than the Xeon with a much smaller demand.
AMD K6-2 & Cyrix/IBM CPUs: These chips only allow the use of the old
socket7 motherboards reaching the end of their usage. The ALi chipset for the Super
socket7 boards is problematic to provide 100mhz bus speeds and do not support the New Riva
TNT fast video cards. For these reasons I do not recommend this as an upgrade solution.
Celeron PentiumII: These are economical solutions to moving to the BX
chipset that allows wide channels of data movement across the motherboard, but still lack
sufficient L2 cache to provide all the speed the CPU can provide.
Classic PentiumII (also known as Klamath): This is the best choice today
for upgrading or new computers. The BX chipset makes these CPUs real performers and also
provides for future upgrades to at least PentiumII 800mhz CPUs in the future, (Bios
upgrades may even expand the life of the motherboard further).
Xeon PentiumII: Due to price alone these CPUs are far too expensive for
use in a home system or work station. The increased L2 cache is not necessary for any
application except that of a server.