Nobody Can Answer My RAM ? Too Technical?

[EasyFast]

you guys are awsome! I think I'm going to like this board http://www.sysopt.com/forum/smile.gif

Perhaps I was just over-complicating the issue of speed. My brain just never seems to be happy unless I know the details of how things work.

I really learned a lot from all of your posts! So "SpookyEddy" if I understand this correctly?:

1 / Hz = sec

that would be why the PC66 is rated at 11ns! Therefore, running the PC133 on a 66mhz Buss will give it the same 11ns "AND" the same performance as the PC66! Which answers my question as to if it will hurt the performance of the system to run the PC66 and the PC133 mixed together.

So the answer to that question is "NO" it won't hurt performance!

And to take it another step further, adding more RAM will help the system perform better, therefore I should do it "YES"!

OUCH! I think I am thinking to much! Hehee!

Thanks everyone, it was a great lesson for me!

[SpookyEddy]

Yep thats right.

Makes sense really as Hz is "cycles per second" and the ns value for RAM relates to "number of seconds per cycle". Inverse see, I just had to remember some math http://www.sysopt.com/forum/smile.gif

More RAM is always good, I run 320 meg on my linux box http://www.sysopt.com/forum/smile.gif

Glad we could help.

Regards

Eddy

[Bovon]

Just to 'muddy' the water a bit more, hz, used to be designated as cps. This was cycles per second. so, using the same anology, 1 cps = 1 cycle, or..in todays terms, 1 hz (hertz, so named after the German Physicist Heinrich Hertz, the gent that discovered that radio waves in an antenna was/is an alternating current.)

[EasyFast]

I don't want to sound offensive, but nobody seems to be able to answer some basic questions! For more history on my question, see my post here

First off, Thank to all who have offered their suggestions, I really do appreciate it.

My question would be; Does PC133/7ns RAM degrade itself to 66mhz "AND" 11ns speed when put into a system with a FSB of 66mhz?

It seems to me, there are two different ratings on speed for a chip. MHZ and reaction time in NS. What is the relationship to each other?

If I mix PC66/11ns with PC133/7.5ns will the system run slower because of the 11ns RAM or faster because now there is 160Megs instead of 128Megs?

I know already that PC133 will run at 66mhz and in that regard it makes no difference. But it would seem to me that a system is only as fast as it's slowest part, and droping in 11ns RAM against 7.5ns RAM will in "itself" slow the system, regardless of the extra RAM or the FSB speed.

Both RAMS work together in my system, I have tried it.

BTW: I can't run this board at 100mhz. I am currently running at 83mhz with no problems. Heat is 31C Max.

And where would I find sisofts Sandra around here? I am new to this place!

Thanks everyone!

[EasyFast]

opps, sorry forgot link to more detailed info on my situation, which is explained in another thread
http://www.sysopt.com/forum/Forum1/HTML/015754.html

Hope this shows up http://www.sysopt.com/forum/smile.gif!

[SpookyEddy]

If you dont want to sound offensive don't http://www.sysopt.com/forum/wink.gifj/k

RAM speeds are purely a measure of quality, the motherboard decides what speed they are run at.

As a result RAM should be run at the speed of the slowest dimm, if you have a PC66 & a PC133 then run your FSB's at PC66 or your machine will crash all the time as half your RAM will be running out of spec http://www.sysopt.com/forum/smile.gif

The "ns" rating is just a different way of measuring the quality of RAM so is interchangable with the Mhz value. It is still the motherboard that sets the memory speed.

Hope this helps

Regards

Eddy

[Bovon]

Also, be aware that some of the old chipset mainboards will not run with todays high density ram.

If it will, and a stick of EDO and a stick of PC133 is installed, the PC133 will run at EDO speeds.

If the mainboard chipset will run PC133, and thst is all that is used, the PC133 will process data a little faster than the EDO would, but it will not be very noticeable due to the 66 mhz bus speed bottleneck.

[SpookyEddy]

Just out of interest:

1 / Hz = sec

eg

1 / 133,000,000 = 7.5 * 10^-9

therefore

133 Mhz = 7.5 ns

[GroundZero3]

you will notice an increase in preforamce even if the 133mhz ram is running at 66mhz.

your computer will not have to resort to virtual memory (which is slower of coutse) as much as it has to know since you upped your ram. you will be able to open more programs and what not and your preformance will not degraded.

JaYsin

[BBA]

There is nothing super technical about that question.

Ram speed rating is simply that...a rating. The best analogy I can think of is MHz to MPH.

If I have a set of tires rated to run at 133MPH, yet I only drive at 66 MPH, the tires are only being used at 66 MPH.
It's that simple.

you will notice an increase in preforamce even if the 133mhz ram is running at 66mhz.

Your statement is misleading. The only benefit he will see is by meerely increasing the amount ( not quality ) of ram by the addition of another stick of memory.

If the FSB running at 66 MHz, it is running at 66 MHz and so is the memory. There is no current chipset that runs RAM at a higher than FSB speed. There is no desire for one that does that either. There are chipsets that run memory at a lower speed than the FSB, but not higher.


[This message has been edited by BBA (edited 09-01-2001).]

[Psycho Logical]

There is no direct correspondence between the nanosecond rating of the DRAM chips on a DIMM
and the PCxxx compliance for that DIMM, because there are additional factors like latencies and
lead-off times to be taken into consideration. The numbers are related, but not actually interchangable.

For example, the PC100 specification, developed by Intel, calls for 8ns DRAMS,
but that converts to 125MHz, not 100MHz. Also, PC66 requires 10ns, equivalent to 100MHz.
From these examples, it seems like 7.5ns is cutting it pretty thin for 133MHz.

For more detail and more geek-speak than you can imagine, go here (http://www.pcguide.com/art/sdram.htm) , and click the
"Understandng SDRAM Timing Specifications" link in the left-hand pane.


[This message has been edited by Psycho Logical (edited 09-02-2001).]

[EasyFast]

Got it! See, I learn something new everyday http://www.sysopt.com/forum/smile.gif Thanks!

I want you guys to answer my posts for now on http://www.sysopt.com/forum/smile.gif So when you see my name on post, make sure to stop in to clear things up.

I understood the Buss speed issue, but I didn't understand the relationship between mhz vs. ns. Everyone kept going back to the buss speed point, which was driving my crazy! I really just wanted to know why, so I could come to my own conclusion. Now it makes perfect sense! And you guys explained it in very simple terms. Nice!

[radio1_mike]

Yeah.

A XXX MHz rating is the speed limit of the front side bus on the motherboard that particular stick will run at. You can run slower, and in some cases you could run faster.

A X.Xns rating is the speed of the memory itself, how fast it can be accessed (read from, written to, etc...).

Hope this helps.

[Nighthawk]

BBA, some VIA boards will let you run the memory asynchronously both up and down (I do this at home, P3 700/100 and 640mb of PC133/133). My P3V4X (Via Apollo Pro 133A) has 3/4, 1/1, or 4/3 operations.

It's supposed to increase memory bandwidth, but I didn't notice much of a difference.

There are other things that could factor in your adding more RAM & performance. Some chipsets have addressing/density problems (so they won't see some/all of the new RAM) or caching problems (adding memory to my ALi Aladdin V actually slowed the system down).

I'd benchmark, then add the new RAM, then benchmark again. That's the only way you are going to know for sure what the speed change is.

[This message has been edited by Nighthawk (edited 09-05-2001).]