mem question

[cougar214]

i was wondering if someone can tell me how to figure out what my memory speed is.....i have 2 kingston pc3200 400mgz chips in my pc........i used cpu-z to get my clock speed and it says its running at 166.7mgz.....can someone tell me how to do that math on this?.......i used to know how but forgot.

[_damien_]

PC3200 is the theoretical bandwidth in MB per second (3200MB for each channel). DDR400, or 400 MegaTransfers per second is the rate at which 64 bit chunks are read/written. DDR-memory sends/receives two chunks per core clock, so DDR400 equals a "real" clockrate of 200 MHz.

Your sticks are rated at 200 MHz, so your memory speed is slower than stock ATM - 166 MHz equals DDR333. What system do you have?

[cougar214]

im running a p4@3.06ghz HT not overclocked with an msi pe neo 2 mo/bo.....my fsb is 133.3 and my bus is 533.4...i just rechecked my ram and it is pc3200/ddr400......could there be something wrong somewhere? or did i get screwed on the ram.....hell of a time to find that out.....i got this ram like 3 years ago....lol.....i just been going through my pcand optimizing everything and though of my ram.

[_damien_]

Sounds like you're using the 4:5 divider, which is probably the best choice for your system. The RAM's rating only reflects its certified speed - the FSB and divider will determine the actual RAM speed. I don't think anything is wrong.

[raven]

Everything that damien is saying is true, and so I will just elaborate a bit more.

What you have here is a P4 with a 533MHz FSB speed. Since on a P4 the Front Side Bus is quad pumped, that is where you get 533MHz from. Therefore your computer has an original Bus speed of 533MHz / 4 = 133.3MHz. With a Pentium 4 of a 533MHz FSB, a memory speed of 133MHz was needed to be able to run everything on a 1:1 (FSB:Memory) divider. All that means is that your memory and pre-pumped FSB would both be running at 133MHz. Back then, the memory standard was PC2100 (aka DDR266) which, since it is DDR (Double Data Rate) you divide 266MHz / 2 to get the original speed of 133MHz. With PC2100 RAM, you were able to run everything with a 1:1 ratio.

Now, you have in your computer PC3200 RAM (aka DDR400). This has an original speed of 400MHz / 2 = 200MHz. Currently, with a P4 which has an 800MHz FSB (200 * 4) you would need a stick of PC3200 to be able to run at a 1:1 ratio. In your case though, you can still run at a 1:1 ratio, but your RAM would be downclocked to DDR266 speeds (133MHz). To use this to your benefit, you can use a FSB:Memory divider to maintain a 133MHz FSB and just up your Memory speed as damien pointed out. This is in fact what it looks like it being done already. Since your memory speed is 166MHz, we can just do some math and we can determine that you are on a 4:5 FSB:Memory divider. (166MHz(memory speed) / 5) * 4 = 133MHz FSB speed. If you had a 2:3 divider option on your board, you would be able to run your memory at 200MHz, while still keeping your FSB at 133MHz and your computer at 3.06 GHz.

Another option to boost your memory speed, using the divider that you are on, is to increase your FSB which would inturn also increase your CPU clock. Right now, your CPU speed is calculated using a fixed multiplier of 23. Therefore you can see that your current CPU speed is just the product of your multiplier and your FSB (23 * 133MHz = 3.06GHz). If you increase your FSB and keep the same 4:5 divider, then you will both increase your FSB, CPU and Memory speed. This is because the FSB is related to both the CPU speed and the memory speed.

To gain full use of your PC3200 RAM, while keeping a 4:5 divider, you would have to increase your FSB to (200MHz / 5) * 4 = 160MHz (or a quad pumped FSB of 160MHz * 4 = 640MHz). Inturn this would also overclock your CPU to a speed of 23 * 160MHz = 3.68GHz, but since this is a totally different topic to be discussed, you can find more information on it using the search tool implemented in the forums. Or just ask, and I will take some time to explain things further.


Raven

[cougar214]

im sorry guys you have to treat me as though i was an idiot because with this.....i am...i dont know enough about overclocking and at the same time i dont understand it fully....for these reasons i will not attempt to overclock my system in any way...its safer that way.....lol.....but basicly what you guys are trying to tell me is my system is running the way it should be?....also i would like to ask another question.....you already know what im running for ram now......i was offered 2 sticks of OCZ ram at the same speeds..pc3200 ddr400....if i put these sticks in my pc will they work or do i have to use kingston ram to increase my ram speed?.....thank you guys a bunch.

[cougar214]

one more thing....i went into my bios to the frequency/voltage control section and it reads as folows:

dynamic overclocking......disabled
performance mode.......slow
cpu ratio selection......locked
dram frequency......auto
spread spectrum......enabled
ddr clock.......333.......(also blacked out so i cant touch it)
agp/pci clock..........66.66/33.33
cpu vcore ajust.......no
cpu vcore........1.5250v
ddr power voltage.........2.60v
agp power voltage........1.50v


If i were to change the performance mode to fast or even turbo would that make my system run faster or unstable?.....or none of the above?

[raven]

im sorry guys you have to treat me as though i was an idiot because with this.....i am...i dont know enough about overclocking and at the same time i dont understand it fully....for these reasons i will not attempt to overclock my system in any way...its safer that way.....lol.....but basicly what you guys are trying to tell me is my system is running the way it should be?....also i would like to ask another question.....you already know what im running for ram now......i was offered 2 sticks of OCZ ram at the same speeds..pc3200 ddr400....if i put these sticks in my pc will they work or do i have to use kingston ram to increase my ram speed?.....thank you guys a bunch.

In short, yes, your system is running the way it is supposed to. To be able to run DDR400 Memory at 200MHz, you would need a P4 with an 800MHz FSB running with a 1:1 FSB:Memory divider.

To answer your latest question, since all sticks of RAM would be running lower than there intended speeds, it will be no problem at all to stick in the extra OCZ sticks if you have room. If your board is running in dual channel, then all 4 sticks would have to be of the same size. In any case, the one true way to find out, is to stick the OCZ in there, and check with CPU-Z.

If i were to change the performance mode to fast or even turbo would that make my system run faster or unstable?.....or none of the above?

Since I do not have any experience with your motherboard, I would suggest that you try it out, and see if there is any performance boost. To measure your performace, you could use SiSoft's Sandra (http://www.sisoftware.net/) memory benchmark to see if there are any improvements. First, run the test before you make any changes, and then run it after you do make changes. Incase your computer does not POST, then just be sure you know how to clear your CMOS (reset your BIOS). Usually this is done with either a jumper on the motherboard, or the removal of the CMOS battery, or the pressing of a certain key on the keyboard. This information can be found in your Motherboard Manual. But, since your memory will not be running faster than it is intended to run, I do not forsee any problems. (but it is always good to have a back-up plan, or know how to revert everything to the way things were in case you mess up).

[cougar214]

yes all ram in question are 512 sticks.....the kingston and the ocz.