I currently have a P4 533Mhz mobo. Unfortunately, this is rambus, and there doesn't seem to be a great deal of support for it any more (not on desktops at least). I heard that Intel wern't going to support it any more on desktops. It's much cheaper for me to upgrade to a new P4 motherboard and DDR than buy more rambus, which I sorely need (I only have the 256Mb that came with the board as I figured it would get cheaper - ). The new boards are of course 800MHz, they're backward compatible with my 533MHz processor, but will the PC3200 DDR be compatible with my processor? What I mean is, will I be able to run the processor at 533MHz and the RAM at 800MHz. I think it's impossible. What's more, will DDR400 (800MHz) even be compatible with my 533MHz P4? I.e., can I run the DDR400 at 533MHZ instead of 800MHz? The mobo in question is the Gigabyte GA-SINXP1394. I can't find anything out about this problem. I was wondering if anyone had done this, or could tell me anything at all . Thanks.
You can run RAM and processers at lower speeds without much of a problem. But remember, you won't get any real benifit from the higher speed ram, other than a higher amount of RAM. You can try to overclock, but even then you'd need some serious cooling.
1. Your 533MHz FSB Pentium 4 is actually running at 133MHz FSB transferring 4 bits per clock cycle. 2. An 800MHz FSB Pentium 4 is actually running a FSB of 200MHz. 3. RAMBUS is different to DDR, PC-800 Rambus runs at 400MHz, PC-1066 at 533MHz. However this has no effect on what type of CPU you have, you have a Socket 478 CPU that will plug into any current Pentium 4 motherboard. 4. PC-3200 memory is capable of running at 200MHz (hence in synch with with the Pentium 4 FSB). DDR-400 comes from the dual data rate, i.e. it is effectively like 400MHz single data rate memory. PC-3200 is the numbers all added together, 64-bit memory bus (divide by 8 to change to bytes) x 200MHz clock x 2 bits transferred per clock= 3200Megabytes/second. 5. You can buy a Pentium 4 motherboard that supports 533MHz FSB CPUs, boards based on the Intel 845, 848, 865 and 875 all do and it will run your CPU quite happily. 6. You could chuck in DDR-400 memory and it would run it at DDR-266 speeds, the rating merely suggests it is capable of running faster. 7. Some boards may let you run the memory asynchronously with the FSB, i.e. faster. However the benefit is likely to be small as the FSB is the bottle neck! 8. Scan are offering 256MB PC-1066 RIMM (2 x 128 I think) for £71.86. Intel is moving to DDR-2, Socket 775 and PCI Express this year so upgrades now have no future proofing EDIT DABS to here
