How much better is RAMBUS over DDR

[WaTaGuMp]

I was just looking at Pricewatch and can get 512mb of Samsung RAMBUS for $156.00. I am running Crucial 2100 DDR right now. Is it worth the money to get the RAMBUS right now I am not overclocking the system and curious if I should get it if down the road I overclock it. Also ECC or non ECC?

 

[Duvie]

Well IMO the rambus is better if you are not ocing....

PC800 will do like 2450mb/s, but you could surpass that if you could get pc2100ddr to 333mhz...then you would get about 2500+mb/s (it is what I am getting)

This ofcourse would put you just comparable to the rdram...If you oc therdram ofcourse you will pull ahead of the oced pc2100 again...

IMO a good i845d mobo with good amount of memory ratios and at high fsb (ie w/ a 1.6 northwood) you can get above default rdram scores...OR, my recommendation a sis645 chipset with pc2700 ddr (preferrably 5ns as this should allow you to go up to 400mhz plus). It is feasible at high mhz cpu and fsb you could get near 3000mb/s and only a bit below new pc1066 scores. With this speed and board it is likely you could stay neck and neck with rdram pc800 as it likely at a point couldn't make the ocing of the pc2700...

 

[WaTaGuMp]

Well right now I have a Northwood 2.0 with a Soyo Fire Dragon mobo the best it will overclock to is 120 fsb. As for right now I am not too happy with the overclocking results with this mobo. I keep waiting to see someone with this combo pull off a good overclock, but all I see is the Asus 266 board and Abit TH7 getting thee big overclocks. It is my own fault because I didnt do my research on this mobo before buying it. Its not that it doesnt run well or stay stable ut in the overclock department it pretty much sucks IMHO. I am kicking myself for this decision cause when I got the mobo Frys also has the Asus one but I didnt bother to look at the time. I trusted the salesmen cause when I bought my last upgrade it did pretty well. Now back to the topic you say I can get better scores with the RAMBUS, but will I notice any difference other then some numbers that say its faster etc etc?

 

[Duvie]

Ok...p4 2.0ghz only getting 120fsb!!!! Well that is about the limit of these...Remember all these 1.6,1.8, and 2.0's are coming from the same lot but beinmg downsized to fill market demand...INtel gets good yields on all of them...

average ocs per chip

1.6 w/ 150fsb for 2.4ghz

1.8 w/ 133fsb for 2.4ghz

2.0 w/ 120fsb for 2.4ghz

see a pattern????

if you take that board and run it on my asus p4s333 (sis645 with pc2700 support) setup now you would be able to run a 3:5 ratio for the memory and run memory at 400mhz ddr....take pc2700ddr and it should get there and give you memory scores of around 3000mb/s...way over the top of default rdram and likely very close to oc'd rdram...Pc1066 at default is supposedly to be running at 3300mb/s...

 

[Duvie]

Notice any differences????

That depends on the programs you are running....Some like cpu raw power like seti and divx encoding...others like memory bandwidth like some 3d games...It depends...

General snappiness and running the internet....I doubt you could notice...

 

[WaTaGuMp]

I also only get 1900 scores in my memory tests from Sandra. That is also running at cas 2 timings.

 

[WaTaGuMp]

Hey thx for you info bud, I am also familiar with the overclock power of those 1.6 chips Whoooooahh. I just wish I could get to 150 fsb thats some real speed jumps there. I had my old system at 150 fsb and was very happy with the performance gains. But if what you say is true about 120 being about the limit fsb wise for my chip then its not a big deal. I am just anal like that LOL.

 

[XBoxLPU]

I think to get the most bandwith with DDR .. you would have to go with PC2700.

 

[Duvie]

It sound like at 120fsb you have likely got memory speed set to auto or 1:1 ratio...that means your memory at 120fsb is running 240mhz or 26mhz below pc2100 specs and thus why you don't even get 2100mb/s in sandra...see if the board offers another ratio like 3:4 or 4:5...

3:4 would give you 160 or 320mhz....maybe if your memory is crucial pc2100 you can adjust the ddr voltage up .1v you could get this...likely score would be 2400's...

4:5 ratio would be 150 or 300mhz...most pc2100 can do this unless total generic crap...likely scores would be 2300's

 

[Duvie]

By the way the 120fsb comment is an average of what I have seen...I have seen some do more and some less...

Have you even offered it a voltage boost???

 

[WaTaGuMp]

The system is not over clocked right now so its at default of 100mhz.


As for the settings my board offers I have these at the following settings.

Memory frequency set at DDR266

DRAM Timing set at 2

Active to Percharge Delay at 5 thats the lowest

DRAM RAS# Percharge at 2 the lowest also

 

[WaTaGuMp]

Yes I have upped the voltage.

 

[Duvie]

nothing about memory ratios???? Hmmm....My msi ultra ary i845d mobo was like that and after like 122fsb it reverted back to a 1:1 ratio, but prior to that it most have been a 4:5 ratio as more score at 122fsb were at 2300's, but at 125fsb they went down to 2000's...

Check the webiste maybe there is a new bios to add some ratios....


I guess I am finding out more and more why Asus is king when it comes to overclockability.....

 

[Duvie]

At 100 and setting to 266ddr the board is likeluy running a 3:4 ratio 100fsb=133memorty for 266mhz ddr...

However the mystery is at what point does this ratio shut off and lock??? INot all boards are manufactured for the likes of the northwood...Who knew the fsb speeds that would be reached with a locked multiplier....

Play around...try 105fsb,110,115,120 ans see if at auto or 266ddr the memroy scores get bigger or start to hold steady...


Over 122fsb on my old msi board it became 1:1 ratio regardless if I set it to 200mhz ddr, 266ddr or auto....Need bios support likely...

 

[WaTaGuMp]

Kinda why I think this board sucks for overclocking. As for a BIOS for it I have only had the board for 2 weeks should be the latest BIOS for it. But I will look it up.