ASUS P4T533-C memory question

[callix]

Hi all!
I got a P4 2.66Ghz 533FSB with 2x256MB 1066Mhz Samsung RIMMs.
The board is ASUS P4T533-C. The FSB is at 133 so 20X CPU multiplier gives 2.66Ghz CPU clock, while RIMM is running at 8X the FSB at 1066Mhz.

I got a chance to get 4x512MB 800Mhz ECC Infineon RIMMs for cheap and am willing take the hit in terms of RAM refresh rate from 32ns to 40ns. 1066RIMMS will be taken out altogether.

My question is: since 800Mhz RIMMs use FSB of 100Mhz, how will my processor respond to this? Will FSB fall to 100Mhz and the CPU will slow down from 133MhzX20 (2.66Ghz) to 100Mhzx20 (2Ghz)? Is a 2.66Ghz Northwood processor compatible with 800Mhz RIMMs any way?

Many Thanks in Advance!
callix

 

[BonzaiDuck]

Is this the P4T533 motherboard that uses 32-bit, 232-pin Rambus modules?

If it is, you want to be careful that you don't socket 16-bit RIMMs by mistake.

And if it is the P4T533 or P4T533R, I have one. It has the 533 FSB.

Also -- if this is the same P4T533 board that I have, it only has two memory slots, if I recall. I eventually replaced my 2 x 256MB configuration with 2 x 512, and 1 GB is about as far as it goes on that one.

 

[callix]

Hi! It's P4t533-c, it has 2 banks of 184pin, 16 bit memory. Each bank can take maximum 1GB - 2X512MB.

 

[RanDum72]

It should be fine. It will run asynchronously, the CPU will still run at 133mhz FSB and the memory will run at 100mhz. Its a good thing you got 40ns RIMMS because thats the only RDRAM 800 that will run with 1066fsb CPU's (45ns is good only for 800mhz FSB).

 

[BonzaiDuck]

That's more info than I could've offered him. I think my own P4T533R would run 32-bit PC800, but I grabbed the PC1066 modules right away. I built that system in early 2003, and it's been relegated to duty as a file and scan server. That was about when Intel decided to dump Rambus and go "DRAM." I don't think anyone ever met the promise of producing 1GB modules for that board, or if they did, I wouldn't have paid the asking price for them.

 

[RanDum72]

The Intel 850E chipset also has limitations. Its memory can max out at 2gb but only with RDRAM 800. With RDRAM 1066, its limited to only 1.5gb.