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flclisgreat
02-17-2007, 09:58 AM
so why didn't i read somewhere, anywhere at all, that ALL am2 boards change the ram divider based on the cpu multiplier.

cdawall
02-17-2007, 10:14 AM
ALL AMD board since 754 have done that

flclisgreat
02-17-2007, 10:22 AM
ALL AMD board since 754 have done that


didn't know. last rig was a socket 370 600mhz celeron and from what knew they didn't. now i feel dumb

cdawall
02-17-2007, 12:29 PM
im surprised you dont like the tforce 6100 from what i saw they are very good mobos heck the s754 version is the best voltage to clock board 754

i found nemo
02-17-2007, 05:38 PM
not better than dfi 250gb lol sorry i'm boasting. j/p lol

flclisgreat
02-17-2007, 06:29 PM
im surprised you dont like the tforce 6100 from what i saw they are very good mobos heck the s754 version is the best voltage to clock board 754


not the am2 board, it sucks.

ozzimark
02-17-2007, 07:40 PM
so why didn't i read somewhere, anywhere at all, that ALL am2 boards change the ram divider based on the cpu multiplier.
it's not the motherboard. it's the cpu... to be specific, the memory controller in the cpu

since it runs at the same speed as the cpu, there is a divider that sets ram speed from cpu speed. that divider can be calculated as

ceiling ( cpu multi / memory ratio )

where memory ratio is 400mhz = 2/1
333mhz = 5/3
266mhz = 4/3
200mhz = 1/1

so if i set 9x cpu multi and 333mhz ratio...

ceiling ( 9 / 5/3 ) = ceiling (5.4) = 6

so then the ram runs at cpu/6 :toast:

flclisgreat
02-17-2007, 07:42 PM
it's not the motherboard. it's the cpu... to be specific, the memory controller in the cpu

since it runs at the same speed as the cpu, there is a divider that sets ram speed from cpu speed. that divider can be calculated as

ceiling ( cpu multi / memory ratio )

where memory ratio is 400mhz = 2/1
333mhz = 5/3
266mhz = 4/3
200mhz = 1/1

so if i set 9x cpu multi and 333mhz ratio...

ceiling ( 9 / 5/3 ) = ceiling (5.4) = 6

so then the ram runs at cpu/6 :toast:

so lost. lol. anyway, mobo only has 4 options, 400, 533, 667, and 800 for the ram.

mAJORD
02-17-2007, 09:09 PM
http://www.xtremesystems.org/forums/showthread.php?t=105798 :p

With the knoweldge that Ram divider decided by the CPU multiplier, that table shouldn't be too confusing.

flclisgreat
02-17-2007, 09:12 PM
yeah it just proved my theory. if ur cpu won't clock, then neither will your ram. it keeps them pretty close

ozzimark
02-18-2007, 07:19 AM
so lost. lol. anyway, mobo only has 4 options, 400, 533, 667, and 800 for the ram.
yeah, notice a trend... 400 = 2x200 which is the 1:1 ratio
533 = 2x266 which is the 4:3 ratio
and so forth. ;)


yeah it just proved my theory. if ur cpu won't clock, then neither will your ram. it keeps them pretty close
yup, this is quite true. lowest memory ratio.. or the fastest one rather, is cpu/5. so no matter what you do, you need at least 3ghz cpu clock to hit 600mhz ram clock. definitely annoying for me when i have ram that can do 600mhz at 2.1-2.2v... and then my cpu just tops out shortly afterwards :slapass:



it's with a low multiplier conroe that good ram is needed to hit high cpu mhz.. with a 7x multi, and a 3ghz chip, they need ram that can do at least 428mhz.. and a lot of conroes clock better than that :p:

flclisgreat
02-18-2007, 07:22 AM
yeah, notice a trend... 400 = 2x200 which is the 1:1 ratio
533 = 2x266 which is the 4:3 ratio
and so forth. ;)


yup, this is quite true. lowest memory ratio.. or the fastest one rather, is cpu/5. so no matter what you do, you need at least 3ghz cpu clock to hit 600mhz ram clock. definitely annoying for me when i have ram that can do 600mhz at 2.1-2.2v... and then my cpu just tops out shortly afterwards :slapass:



it's with a low multiplier conroe that good ram is needed to hit high cpu mhz.. with a 7x multi, and a 3ghz chip, they need ram that can do at least 428mhz.. and a lot of conroes clock better than that :p:



your telling me, i got 2gb's of G. Skill HZ. it rocks and i can't do anything with it in this system. thats ok, i got it @ 4-4-4-5 500mhz. guess i will be going conroe to get this ram movin.

RyderOCZ
02-18-2007, 07:39 AM
your telling me, i got 2gb's of G. Skill HZ. it rocks and i can't do anything with it in this system. thats ok, i got it @ 4-4-4-5 500mhz. guess i will be going conroe to get this ram movin.500 MHz, is that what you see in CPU-z?

That is DDR2-1000, how much more do you need it to run?

flclisgreat
02-18-2007, 07:58 AM
500 MHz, is that what you see in CPU-z?

That is DDR2-1000, how much more do you need it to run?


yes that is real mhz, not doubled. it needs to run faster, 600mhz maybe 650mhz. then i might be happy

ozzimark
02-18-2007, 08:18 AM
yes that is real mhz, not doubled. it needs to run faster, 600mhz maybe 650mhz. then i might be happy
why? ram speed has such a little effect on overall performance, it's pathetic. worry about getting a faster cpu or running tighter timings. see if you can get 1T stable at 500mhz... it just might be possible. ;)

http://www.eclipseoc.com/image/benching/498.8-start.png


:toast:

flclisgreat
02-18-2007, 08:27 AM
it may be, but not on this mobo. there is no 1t/2t selectable setting. and only 2.1volts to ram.