PC3200 w/ 1.8Ghz P4?

[Jeff Partridge]

I'm in dire need of a mobo replacement for my P4T-E. It locks up and take
about 24 hours before it it even posts, claiming it's been over-clocked and
now starting in safemode. I was looking at the P4P800-E Deleuxe. My
question is, can I use my 1.8 Ghz P4 in it, but buy PC3200 Dual Channel
memory? The FSB on the CPU is only 400 and the PC3200 is supposed to be for
800. Will memory work underclocked? Isn't the speed rating the max the
memory should run at? I'm not financially ready to shell out $160 for 3+Ghz
CPU right now, but I'd like to at least have the memory that will handle one
in the future.
I wish I'd kept up with this stuff, but I've been too busy.
Jeff

 

[Paul]

I'm in dire need of a mobo replacement for my P4T-E. It locks up and take
about 24 hours before it it even posts, claiming it's been over-clocked and
now starting in safemode. I was looking at the P4P800-E Deleuxe. My
question is, can I use my 1.8 Ghz P4 in it, but buy PC3200 Dual Channel
memory? The FSB on the CPU is only 400 and the PC3200 is supposed to be for
800. Will memory work underclocked? Isn't the speed rating the max the
memory should run at? I'm not financially ready to shell out $160 for 3+Ghz
CPU right now, but I'd like to at least have the memory that will handle one
in the future.
I wish I'd kept up with this stuff, but I've been too busy.
Jeff

You can find a downloadable manual here:

http://www.asus.com.tw/support/download/item.aspx?ModelName=P4P800-E Deluxe&Type=All&SLanguage=en-us

Table 2 "Memory frequency/CPU FSB synchronization", tells you
the allowed relationships between CPU and memory. At FSB400, the
automatically chosen speed is PC2100. PC3200 is backward compatible,
and will run at PC2700, PC2100, PC1600. So, no problem there.
And the PC3200 memory will also prepare you for the day you upgrade
to a FSB800 S478 processor.

Supported CPUs - the 1.8a/FSB400 is listed.
http://www.asus.com.tw/support/cpusupport/cpusupport.aspx

You can likely overclock the 1.8a a bit. You might be able to get
2.4Ghz out of it, and at the same time, the memory will run faster
too. PC2100*(2.4/1.8)=PC2800, is still less than the PC3200 rating
of your memory, so the PC3200 will still get the job done.

If you get a copy of http://www.cpuid.com/cpuz.php , you can
determine exactly what speed everything is running at, and can
correlate the BIOS changes you make, to what is really happening.

HTH,
Paul

 

[Jeffery Partridge]

Thanks Paul.
I suspected as much, but I didn't know for sure. I'm glad I can upgrade a
few steps at a time, instead of having to buy the cpu right now too.
Jeff

 

[Ben Pope]

I'm in dire need of a mobo replacement for my P4T-E. It locks up and take
about 24 hours before it it even posts, claiming it's been over-clocked and
now starting in safemode.

Are you sure it's the motherboard at fault?

If it's something like the PSU or dodgy contact on the RAM it would be
an expensive way to find out. Try reseating your RAM a few times, and
checking your voltages if possible.

If you do want to go to a faster CPU at some point, then a new
motherboard will be required anyway, so if you can use the new
motherboard with your old kit, that would seem like the right way to go.

Ben

 

[Jeffery Partridge]

I know it's the motherboard by now because I've removed EVERYTHING from the
board when it was not booting and it gave no errors that there was no RAM or
CPU plugged in. When it is acting up (as it is right now, down for 30+
hours), the keybaord doesn't even get power. I just put a brand new power
supply in it, but had tried a different one first anyway.
There was a posting here that suggested that maybe the holddown was exerting
to much downward force on the cpu and was warping it. When I checked, this
WAS indeed the case, I have a very pronounced extrusion on the bottom of the
baord under the cpu, so this may be the problem. Since the board is already
warped, I'm not going to try to fix it anymore. Unfortunately, I've got
RDRAM, so it's useless in new mobos. The new memory is where the pennies go
i replacement of my system.