Question about new memory UPDATE help needed

[blackangst1]

Hi all

So I replaced my 2 x 1 memory with 2 x 2, and installation went fine. Two things that are odd, but not deal breakers-
*First-when I leave everything at default settings EXCEPT command rate (I switched it to 1T) it wont post. Mem test ran fine for 2 hours.
*Second-when I look in my BIOS, it is seeing it as 800MHz, but it defaults to 4:3 ratio for some reason.

Other that that it seems fine. I am replacing DDR2 533MHz with DDR2 800MHz. I got Patriot PDC24G6400ELK 2 x 2 5-5-5-12.

Any ideas?

 

[JustaGeek]

It is hard to determine exactly what is happening here without knowing your computer's specs, but I'll try...

If your RAM is actually running at 800MHz, and your RAM/FSB ratio is 4:3, your FSB must be 300MHz. Otherwise, it will run below 800MHz. (e.g. with FSB 266MHz x 4:3 = 355 x 2 = 710MHz memory speed).

Example based on my computer, with the 16/13 ratio:

FSB 325MHz x 16/13 ratio = 400MHz Memory bus x 2 DDR = 800MHz memory speed.

But my NVidia chipset allows me to run the FSB and Memory bus "unlinked", for (theoretically) unlimited number of memory multipliers (dividers). Some Intel motherboards might be limited to only a few basic fractions, like 3:2, 4:3 etc.

Verify your actual RAM speed with CPU-Z, and choose the most appropriate memory multiplier available.

Good luck!

BTW, 1T is generally not recommended on Intel platform, with 2T being much more stable with only a minimal bandwidth loss.

 

[blackangst1]

Originally posted by: JustaGeek
It is hard to determine exactly what is happening here without knowing your computer's specs, but I'll try...

If your RAM is actually running at 800MHz, and your RAM/FSB ratio is 4:3, your FSB must be 300MHz. Otherwise, it will run below 800MHz. (e.g. with FSB 266MHz x 4:3 = 355 x 2 = 710MHz memory speed).

Example based on my computer, with the 16/13 ratio:

FSB 325MHz x 16/13 ratio = 400MHz Memory bus x 2 DDR = 800MHz memory speed.

But my NVidia chipset allows me to run the FSB and Memory bus "unlinked", for (theoretically) unlimited number of memory multipliers (dividers). Some Intel motherboards might be limited to only a few basic fractions, like 3:2, 4:3 etc.

Verify your actual RAM speed with CPU-Z, and choose the most appropriate memory multiplier available.

Good luck!

BTW, 1T is generally not recommended on Intel platform, with 2T being much more stable with only a minimal bandwidth loss.

Thanks geek I'll check it out.

 

[blackangst1]

OK here's some details. I cant figure out what I'm missing. My system: Abit AB9 Pro mobo, CDC 6400, http://www.patriotmem.com/prod...oupid=38&id=593&type=1">Patrot 2 x 2 memory (also listed in original post).</a> Not sure my HD, etc is relevant. Im running Vista 32 bit. My bios is Phoenix v6.00PG 8/16/07. Both Windows and BIOS are seeing 4gigs.

Here's what Im seeing in my BIOS (BTW it's default booting @ 544) (not overclocked):

external clock 272

multiplier x9

N/B Strap CPU as: by CPU (set as default)
*my choices are:
Core Freq / PSB
133MHz / 533
200 / 800
267 / 1066

DRAM SPEC - Auto (set as default)
*my choices are:
DDR2 533 which gives me 1/1
DDR2 667 which gives me 4:5
DDR2 800 which gives me 2:3
*shows DRAM clock @ 408MHz

DDR2 voltage: 2.0v

All timings are set to auto.

CPUZ is seeing same thing:
DRAM freq 408MHz
FSB : DRAM 2:3
5-5-5-12 (rating of memory) 2T
---------------------------------------------------------------------------------------------------

Well Im not sure what else I can provide. I have read some BIOS's have a "secret menu" for lack of better terms that gives more choices...maybe mine does? No idea. I have cleared my CMOS and above results are what it boots at. I have flashed BIOS from a previous BIOS date of 12/06, and I honestly cant see a difference.

Ideas please? I know something isnt right but I cant find it /cry

 

[JustaGeek]

I don't think I understand your problem.

The CPU-Z shows everything properly. I don't know why, but your FSB is running at 272MHz, which is slightly higher than the stock 266.6MHz. You can adjust it manually to 266 or 267MHz.

With the 3:2 ratio, and 266.6MHz FSB, your RAM will be working at 2x400 = 800MHz.

But it should be fine at 2x408=816MHz too, so if you are stable, don't worry about these little discrepancies.

 

[blackangst1]

OK thanks geek. It was odd to me my memory wasnt running 1:1.

And Im stable so I'll let it be. Thanks again.