Can you use DDR333 on *any* i845 Mobos???

[Styler2K]

Hello,

I was just wondering if there is such a thing as a motherboard based on the Intel 845x chipset that can support DDR333 RAM?

Till now, I've only been able to find SiS based ones that can.

Any help would be greatly appreciated.

Thanks!

 

[Lizardman]

any mobo that uses DDR mem can use DDR333 memory. Its just not "officially" supported.

 

[brunswickite]

i845 and i 845e does not support ddr333 officially or unofficially

i845g supports ddr 333 unofficially

intel branded i845g mobos dont support ddr 333 i think

 

[Styler2K]

Thanks for the reply guys...

But I think I need some clarification;

While the Intel 845G does "unofficially" support DDR333, how would the performance compare to say a SiS645 board that claims to support "officially" DDR333 RAM?

More specifically, let's say I'm looking at two motherboards... The ASUS P4S533 and the Gigabyte GA8IGXP.

If I put a stick of 512 DDR RAM (DDR333) on both boards, how would the level of performance compare without any overclocking?

Thanks again!

 

[klc314]

I think if memory bandwidth were the only consideration, the performance would be better with any board supporting DDR333. However, there are a lot of other factors. The Asus P4B533-E will support DDR333 without overclocking the CPU, and only slightly overclocking the memory. I think stability is important, but a lot of boards will overclock and remain stable for quite a ways above the processor's rated speed. Most of the 845G boards will support DDR333 without much work, and whether or not it's officially supported is kind of a moot point.

 

[MacKenzieIII]

Ok.... as it has been said. You can run DDR333 memory on any motherboard that supports DDR.

The catch is that if you want to run your DDR333 memory (PC2700) at that speed (DDR333) you need to know what kind of ratios your motherboard supports.

Most 845E motherboards have a 2.0x and a 2.66x.

Officialy 845G motherboards are supposed to have the same, but some will give you the option to have 2.0x and 2.5x

What these ratios mean is that on an 845E at fsb100 your DDR memory can be run at DDR200 or DDR266. (100x2.0 = 200 or 100x2.66 = 266)
or at fsb133 your DDR memory can be run at DDR266 or DDR353. (133x2.0 = 266 or 133x2.66 = 353

But those are just standard FSB. If you dont mind overclocking and your chip can handle it.
you could have say fsb125 and use the 2.66x ratio and you get DDR333 (125*2.66 = 333).
or maybe you want fsb166 and use the 2.0x ratio and you get DDR333 (166*2.0 = 333).

Now with the 845G MBs (unofficialy on some of them). Is the 2.5x ratio. This means at FSB133 you can get DDR333 (133*2.5 = 333).

Hope this helps. Also sometimes these #s are writen diffrently. If someone says the 3/4 ratio thats 2.66, or the 4/5 thats the 2.5 or the 1:1 thats the 2.0. Some motherboards display it diffrently.

 

[Lizardman]

Example right now I am running my abit BG7 motherboard with a 166 syncronous fsb, meanning the memory is at DDR333 and my cpu is at 166fsb x 16. hope this helps some

 

[jiffylube1024]

Originally posted by: Lizardman
any mobo that uses DDR mem can use DDR333 memory. Its just not "officially" supported.

correct.

 

[Nafets]

I have been confused about this 'DDR333 on i845 motherboards' topic also.

My questions is, on a motherboard (Intel D845EPT2) that only supports DDR200/DDR266, would there be a performance increase in using DDR333, or would you just be stuck with running the DDR333 memory at DDR200/DDR266 speeds?