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FSB:RAM frequency

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Cho

Member
Joined
Jul 12, 2002
Location
Hong Kong
I have a P4C800 and I want to change the FSB:RAM frequency.
How could I do so?
Should I change in:
BIOS -> Advanced -> JumperFree Configuration -> DRAM Frequency?
But I can only select 266/333/400/Auto in this option.
How can I change the frequency to something like: 5:4 or 3:2?
 
Showstoppermd said:
its been awhile since i played with it but i think it works like this:
1:1 = 400
5:4 = 320
3:2 = 266
So... I can't run the machine with frequency 4:5, right?
 
good question! hehehe but basing on what i have read, i havent seen anybody running at 4:5 so i guess u cant :(
 
4:5 is for AMD mobos only AFAIK.... besides 4:5 is a crappy/weird ratio I tested it on my nForce2 board and I got lower scores than at 1:1:rolleyes:
 
Actually on Intel mobos, the 4:5 and 2:3 ratios are only available for 100/400 and 133/533 FSB chips. It effectively runs the ram faster than the FSB of the CPU. The only time this actually gives you a performance gain is when you don't have dual channel DDR memory.

My Albatron allows all settings (3:2, 5:4, 1:1, 4:5, 2:3) no matter the detected FSB of the chip and even in dual channel mode, but running my memory in dual channel 2:3 gave me zero performance benefit over 1:1 dual channel. The reason? Dual channel DDR running at 1:1 will completely fill the CPU's bandwidth. Anything faster is just wasteful...
 
my computer thinks that my corsair xms pc3500 is pc3200, and i guess i need to adjust the mhz speed, someone told me, is this the correct way to fix this problem, and if so how do i adjust it?
 
r u running at 1:1? or 5:4? hmm but i dont think that made a difference.. hmmm
 
This whole "my board detects my memory speed" and whatnot really ****es me off. Why can't these board manufacturers stop trying to suggest (or even FORCE) speeds, why can't they just say "Here are the multipliers that YOU can choose from:"

That's what my Albatron board does. Not that it's a killer overclocker, in fact it really isn't :( But it just lists the multipliers and doesn't even try to suggest a speed. It DOES give you an area that tells you what the memory speed will be at your selected FSB and multiplier which is nice if you can't do the math in your head.

But if I get in there and tell my board to do 1:1 at 250mhz, it doesn't care if my memory is PC2700. These stupid boards that make you choose between "266, 333, 400mhz" speed options that jack around with the multipliers behind your back are really annoying.

I bring this up because there's a guy in the memory forum who found some killer PC2700 ram that will do 250 (500 DDR) on loose timing and a little extra voltage, but it will only do that in 4:5 mode! Everytime he sets his board to a "400mhz" mode in order to get the 1:1 divider, it always ends up kicking him to a 5:4 divider when he sets his FSB to 250.

Reallllllly irritating...
 
Propilot said:
Hey ciku,
I thought you were getting new memory so you could run 1:1 ?

yup, i got the same type of ram but its 2x512, jst waiting for it to arrive :) I didnt get PC-3500 coz i fear that i might do some mods so i stick with PC-3200 which im sure will run pretty stable like its doing right now :) I'm also waiting for my nb fan to arrive today, as usual, ups is delayed :(
 
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