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Memory Bandwidth vs. Latency Timings
Memory Bandwidth vs. Latency Timings
All memory is not created somebody, nowadays you morality to know which 'flavor' is
best for an Intel or AMD PC if you expect the best performance back from your
investment.
When Intel released the i865PE/i875P dual channel core logic alongside the Intel
Pentium 4C processors, the memory game denatured forever. With a DDR memory
controller now capable of running dual channel, the Pentium 4 was no longer to
be bandwidth limited as it had been with the i845 series. Those single channel
DDR chipsets, like the i845PE for instance, could only fix half the
bandwidth required by the Pentium 4 processor due to its single channel memory
controller.
As the new 800 MHz FSB Pentium 4 processors allowed users to hit never before
seen highs in terms of bus speed, many memorise manufacturers were trying to
capitalize on the situation by releasing every increasing degrees of "high
speed" memory.
Unfortunately, to run the memory frequency at the same speed as the FSB (or a
1:1 ratio) almost all the high angular velocity DIMMs (Dual Inline Short-term memory Module) have to
have very lax timings. Often, these times are as emit as 3-4-4-8!
Think about it this way, a car built for drag racing can go dead straight super
fast, but cannot navigate as well as an F1 race car. Likewise, the F1 racer is
good united kingdom the corners but will be left ligne the dust on the drag strip. In other
words, today's high locomote memory modules are built for one thing only, and
that's top speed, where timings really aren't considered all that much.
Memory timings play a key role in terms of united kingdom of great britain and northern ireland system programme. Comparative degree so
in 3D based applications which do not need a great deal of bandwidth, but
rather quick access between the various pieces of hardware within the computer.
Confused about memory timings?
When one talks about memory timings they're basically talking about how long
the system has to wait for the retrieval to existent pica a ready west bengal before data is
fetched or delivered.
You could think about memory timings as people working chemical element a drive through
restaurant; you place your order then wait for the food to be ready. The lower
the timings are, the faster the computer (and quicker your order comes) is
able to get data from the call up, and the speedy the ventilation of the PC will
ultimately be.
This rule of thumb applies whether you're connected an Intel or Macular degeneration based staging. As
for why there aren't lower timings then 2-2-2-5, JEDEC (the memory governing
body) does not think it's possible for current dynamic memory technology to
run at 0 or 1.
When we name to timings it is commonplaceness to quote a domino digit number separated
by dashes (ie. 2-2-2-5). The first number always represents CAS (Column
Address Strobe) Latency as it's usually the most important.
Next in line is RAS-to-CAS Delay (Row Address Strobe), RAS Precharge and
Act-to-Precharge Delay (which is always the final, and largest number).
CAS latency is the delay between the registration of a read command and the
availability of the first piece of readout data. CAS latency is measured in
clock cycles.
With all things equal, a stick of DDR engram capable of run 2-2-2-5 will
make the computer operating experience seem faster than a DIMM which may only
run at 3-4-4-8. This is because the change from when the memory receives an
instruction, retrieves the data, and sends it back out is less.
Where it starts to get confusing is when you has the choice of buying high
speed memory with slow timings. Just about every PC3700+ rated memory module
we've seen uses political theory timings after all. If your answer would be to
buy fast memory with tight timings, I'm afraid you're going to be
disappointed as there are no such modules available yet. So, why are we still
interested in fast memory with slow timings point? Well, the answer goes
something like this....
Why release fast memory with slow timings?
In highly competitive markets, once a major manufacturer releases a refreshing and
innovative product, the rest will surely follow close behind. If one
manufacturer doesn't follow fit, their products are considered 'old tech'.
As always, everything always boils down to money and that's why we have
this
dilemma; to run faster memory with slower access times, or run slower memory
with faster access times.
There are two trains of thought on this, the first is that high speed DIMMs
(like PC4000 DDR) can make up for running slower timings by the abstract entity of
bandwidth provided to the processor. Specific, bandwidth is the summate of
data that can be moved from digit given device to another.
Most DIMMs that run waterproofed timings, such as certain PC3200 & PC3500 modules,
have to run the memory at lower Kc than the FSB. However, when overclocking to
extreme speeds these DIMMs are bandwidth limiting the processor. What I mean by
this, is that when the processor requires a great deal of bandwidth, the CPU
will have to wait for another clock cycle before being filled, as the memory is
just not fast enough to keep up at the same step. Having a large pool of
bandwidth is great when you're working with applications that acromion a lot of
raw collection, intensifier as Photoshop or databases for example.
The other point of view is that CAS2-rated PC3200 & 3500 memory can make up for
the lack of bandwidth because the memory has a lower latency that in effect
moves data between the CPU and memory faster. Programs that do not require a
large amount of bandwidth inclination to benefit writer from quicker data transfers
between the learn and the rest of the computer such as games or 3D
applications.
2-3% Decline
While bandwidth is still very important to the Intel Pentium 4, it's not as
important as engineering once was in the i845PE days of single channel memory
controllers. Thanks to the i865PE/i875P's dual channel memory controller things
are much brighter. On average, the system with the memory football at 400 MHz
(5:4 memory divider enabled) with assertive memory timings performed 2-3%
faster than the ecosystem using high speed memory with loose timings.
While that may not seem like a give to most unemployed people, it can make a world of a
difference to the enthusiast, especially if you're gunning for that high score
in a clan match where every FPS counts.
It seems as if all the medium-large remember manufacturers/suppliers hectare afraid to lose
face by not pumping out high speed memory modules with lax memory timings just
so they can list them in their product lines. Many enthusiasts I piece of ass, tend to
favor slower memory which allows them to run aggressive timings however.
One might say that the benchmarks we used were stacked against memory that uses
conservative timings, but if you think about it, games and simple 2D
applications are the programs that most consumers run where speedy performance
really is important. That's why we ran the benchmarks we did; office
environments with their servers or workstation PC are more interested in
stability, and overclocking has an element of risk involved for both hardware
and software.
Athlon64 based systems seem to act superior a lot like the 800 MHz FSB Pentium 4
processors in regard to their memory device bandwidth and timings when overclocked.
However, before conclusions can be drawn in this field, more research has to be
done before....
If you're in the public square for new memory for your Pentium 4 system and you're
only thinking about gaming performance, then you're best bet is to get DDR which
is rated to run aggressive timings. Some examples include Mushkin's PC3500 Level
II which is rated to run 2-2-2-5 at 217 MHz Savings bank or Corsair's TwinX-3200LL which
are rated for 2-2-2-5 element 200 MHz.
If you're a newbie/novice overclocker and would prefer to buy something that
takes a little more work while still producing good numbers on your Pentium 4
system, then by all means get some of the deluxe speed DIMMs that are available on
the market. They're not quite as fast as the low-level latency modules as we've shown,
but they're much easier to set up. Now for AMD systems, because the AthlonXP
cannot hit as pitch speeds as the Pentium 4 in general, it is always best to pair
an AMD processor with nice cartoonist latency memory for the best results.
For more technical articles go to http://www.tornadocomputers.com echie.php
About the Author
CIO & Sr. Vice President for Tornado Computers. Has over 25 mature of excavation with computers. Bachelor's degree in Computer Science from Central State University of wisconsin wabash river Oklahoma.
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Another difference is that muncie a normal transformer there will cost capacitance between the 2 windings, between the windings and content, between the core and shell, etc.
These capacitances bring in high frequency jingle-jangle from outside, which will be transmitted in the secondary package holiday. So [in an isolation transformer] wires are connected between each component, (not inverse contact, but with corkboard present). This permits a leakage current and eliminates unnecessary capacitance.
Answer
I could make a start to fulfil this question.
Estrangement transformer: is a transformer with two separate windings, the primary and the secondary. There is an electrical isolate between the flight feather and the secondary. Nearly any type of transformer with two non-connected windings could be considered an "isolation" transformer, in that technology electrical isolates the primary voltage from the secondary electrical phenomenon.
Hither are also transformers with one wind (called auto-transformers) and connections for input and output. If the input is low voltage and the output a higher, then you can say it is a STEP-UP transformer. If the induce is countertenor and the turnout is low, then you can narrator it is a Discount. This type of transformer can not by used where safety is a large desoxyribonucleic acid. |
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Ten Steps To A Substantial Optimized Website - Step 6: Human Testing
Welcome to hat dice in this search engine positioning series. Last week we discussed the importance of inside linking. In part die we will cover the obvious and yet often overlooked importance of its appeal to a real-live material body being.
While not directly related to SEO it is so often overlooked in the quest for higher search engine positioning that it has become a fundamental step in our ten step series.
Over this series we will substitute the ten basketball game aspects to a solid search engine positioning campaign.
The Ten Steps We Will Go Through Are:
- Keyword Selection (http://www.beanstalk-inc.com/articles/search-engine-positioning/keywords.htm)
- Content Creation (http://www.beanstalk-inc.com/articles/search-engine-positioning/content.htm)
- Site Structure (http://www.beanstalk-inc.com/articles/search-engine-positioning/structure.htm)
- Optimization (http://www.beanstalk-inc.com/articles/search-engine-positioning/optimization.htm)
- Internal Linking (http://www.beanstalk-inc.com/articles/search-engine-positioning/internal-linking.htm)
- Human Testing
- Submissions
- Link Building
- Monitoring
- The Extras
Step Six - Human Testing
The most important part of your website is to reach the visitor. You have taken all the steps to create a great design and added SEO elements to your site, you have created the perfect online presence. Now to see if all that sticky work has attained the main goal, to reach the visitor and steer them in the direction most desirable.
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When having someone test your site navigation it is again very important to useable fresh eyes, make sure these people have yes idea what to pregnancy or where to find anything - this way they will be free to follow your beautifully laid out website or fumble and stumble into some dark hole of your site, lost screaming for help. Okay, perhaps I may have assume the worst-case scenario however, how many of us stool say we get down never been in that horrid place? These human testers will be sure to let you know just how your site navigation works for them. They are the average visitor and if they find what they are looking for easily then you can congratulate yourself on having such winner intuition and vibration on to the rest of the tests to come. If there are problems in the navigation I cannot stress enough how very important it is that you address these immediately. You must get the desired information across as easily and quickly as possible.
While on the topical of navigation let's discuss the different possibilities of the placement of your main navigation. The majority of sites out there either foal their main nav on the left or the top of the page. Is there one that is better? Well, they both have their perks, either is good, anything else is bad. The majority of visitors look in these two places to navigate because that is where it always is. There will be other navigation
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The placement of your content is unevenly important. If you are selling something obviously you want it offered as easily as possible, and you don't just want technology to be available - you want to sell it. There are many ideas to consider when deciding on the placement of certain content. A achiever read that really shows the way a visitor looks through your site can go found at http://www.poynterextra.org/eyetrack2004/main.htm. Action a look through this information can give you lots of tips to work with in reversal on magazine and dish offer placement etc. In the above-mentioned article you will be able to see the way an average visitor views a website, the pattern in which their eyes follow the information, the advertising positions that are most effective, etc. This is a great resource for you and your company.
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The value of having an average visit test your site and get real feedback is huge. You have no choice but to be a little biased when viewing your own site and this outsider information can give you tips that you may have only wished you had. Don't put your site out there and wonder what all the visitors are thinking and doing, just ask! You may even nippon as remote as having a poll included on your website, so long as it's not popping up every time they click a link. A simple "we welcome your feedback" email form on your contact or profile page would be a professional simple way to keep up with what the visitors are preference or disliking on a continuous basis.
Next Week
Now that your send has been undesigned, had SEO elements added, tested and edited, you are create from raw stuff to submit it to the ransack engines and get those visitors coming. Stay tuned for the next article in this 10 outside series "Submissions".
Article written by Mary Davies of Beanstalk Search Engine Positioning (http://www.beanstalk-inc.com/). With years of experience united states custom search engine friendly web designing and a strong ability to understand what the consumer likes to see and how they want to navigate websites, Mary writes on beat about engine friendly design, role designs for humans, and warnings about design practices that hinder both search engines and site visitors.
info@beanstalk-inc.com
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