getting 356mhz out of ddr on pc2100 limited 845e?

[BubbaJudge]

I have a gigabyte 8ie533 which is of course, the 845e chipset. i have some samsung pc2700 i want to run on it, but the only memory timings available in the bios are 1.5 and 2.0 of FSB. I have heard mention of a "pin trick" on 845e's to get them to run ddr at 356mhz. is there any truth to this? I have a 2.53 and it seems a waste to have to run ddr266 with it. i know i can OC the FSB and get more than 266 out of the memory, but i will smoke my cpu long before i hit even 333mhz doing it that way.

any help would be appreciated, thx.

 

[BubbaJudge]

i guess i will answer my own question

i found an article here at the tech report where they have unlocked a mysterious 178mhz memory bus on abit 845e mobo's

www.tech-report.com

if anyone knows how or if this can be done on the gigabyte ga-8ie533, plz post

i will post my findings if i answer my own question again.

 

[oldfart]

Running 3:4 and DDR354 is nothing new. I've been running 3:4 on my EPOX 4BDA2+ 845D since February. You have to be careful what board you get. Not all 845D/E boards have that option. By the looks of it, yours doesn't . It looks like you have 1:1 (2.0 option) and 4:3 (1.5 option). Using the way Gigabyte makes that option available in BIOS, you would need one that read "2.67".

Here is something you can try. Underclock your CPU to 132 FSB and see if you get a new option.

 

[BubbaJudge]

you are exactly right, i thought they meant the H/W strapping, i will try the underclock you recommend. whats weird is, in the 8ie533 manual they show a 2.66 setting

thanks for the help

 

[oldfart]

The way it woks is like this. The 3:4 option is in 845D/E board to allow 100 MHz FSB CPU's to run DDR266
100 x 2.66 = DDR266 (3:4 ratio)
or
100 x 2 = DDR200

When you get to 133 FSB, some board makers take the option away, since 133 x 2 = DDR266. They then give you the 1.5 option to slow you mem down to 200 MHz in case you have slow ram.
133 x 2 = DDR266
or
133 x 1.5 = DDR200 (4:3 ratio)

Some board makers keep the 3:4 (2.66) option available at any FSB. Thats how you get DDR354 @ 133 FSB. Others disable it, but it can be tricked (ASUS P4B533) into working anyway.

If not, your best best is to go down one notch to 132 FSB to make 3:4 available.