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Jstyr
04-13-03, 11:32 PM
Can someone explain to me how RAM gets it's bus speed? My Mobo has settings for both the FSB and the RAM bus speed.

However, I thought that the RAM ran at the same speed as teh FSB???

Will raising my FSB effect my RAM as it has it's own bus setting??? I'm very confused on this.

ub3r_n00b
04-13-03, 11:35 PM
Ok there is something we have called timings.. which can set your Ram at a 4 : 5 CPU : Ram ratio making your ram going faster than your FSB.. but if you have that set to 1:1 your ram will be running at the same speed your FSB is.. times 2

Example : FSB set to 100 .... settings 1 : 1... ram running at 200mhz

FSB set to 100 settings 4: 5 ram running at 250 mhz...

I think

-Preet

terrancelam
04-13-03, 11:42 PM
Originally posted by Jstyr
Can someone explain to me how RAM gets it's bus speed? My Mobo has settings for both the FSB and the RAM bus speed.

However, I thought that the RAM ran at the same speed as teh FSB???

Will raising my FSB effect my RAM as it has it's own bus setting??? I'm very confused on this.

some motherboards allow for your to run the ram speed independently of the FSB speed. The FSB speed is linked to the CPU/PCI bus and the ram mhz. The majority of them that I have seen that have that option are the older P3 boards. I didn't seem to notice a difference when I did that option (went from 100/133),

Jstyr
04-13-03, 11:47 PM
Ok my abit board has "CPU FSB- 140"

Then it has "Ratio (FSB, AGP, PCI) set at 4:2:1 respectively."

Then in "Advanced Chipsets" it has DrAM clock settings.
It has the FSB listed and then it has the Memory FSB seperately.

So am I to assume the memory is running independantly?

terrancelam
04-13-03, 11:54 PM
Originally posted by Jstyr
Ok my abit board has "CPU FSB- 140"

Then it has "Ratio (FSB, AGP, PCI) set at 4:2:1 respectively."

Then in "Advanced Chipsets" it has DrAM clock settings.
It has the FSB listed and then it has the Memory FSB seperately.

So am I to assume the memory is running independantly?

No I don't think so, it seems you have the same board as I do. from what I see, you just setting the memory specification type (I.E your just telling the mobo that you have PC2100 complaint ram). The FSB and RAM mhz aren't independent on this board as if you raise the FSB, it also affects the ram speed (if you use a programs like WCPUID it'll show you the true FSB your running at.)

So your can't have your FSB above your ram's clock/maxium speed and still have the ram run at 266mhz.

Mark
04-14-03, 05:44 AM
"Then it has "Ratio (FSB, AGP, PCI) set at 4:2:1 respectively."

that refers to keeping the agp and pci bus in spec, if you were running a 100fsb cpu then you would set it to 3:2:1.

some newer boards have a 5 divider so when you raise the fsb even more the agp and pci bus can remain closer to spec.

i have the same board and with my 2100 mushkin ram i can only get 155 fsb out of it, i am not sure if it is the ram holding me back, or the fact that i don't have a 5 to whatever divider.

terrancelam
04-14-03, 02:19 PM
Originally posted by the snake
"Then it has "Ratio (FSB, AGP, PCI) set at 4:2:1 respectively."

that refers to keeping the agp and pci bus in spec, if you were running a 100fsb cpu then you would set it to 3:2:1.

some newer boards have a 5 divider so when you raise the fsb even more the agp and pci bus can remain closer to spec.

i have the same board and with my 2100 mushkin ram i can only get 155 fsb out of it, i am not sure if it is the ram holding me back, or the fact that i don't have a 5 to whatever divider.

I think it's the physical limit of the actually board (Like how some of the older KT133 chipsets wouldn't go near 133mhz fsb, while the KT133A did.)

LINX
04-15-03, 11:08 AM
on the KR7A u should b able to run 180 maybe a little higher before stuff starts to crap out on u but u will need ur cpu to b unlocked so u can get lower multi's to raise it that high