Toasted CPU?

[Steve Sohn]

I had built my computer on an Asus CUSL2-C with a P3/866MHz chip. This
was a great mainboard, but I needed more performance. Medical problems
precluded building a new machine, so I first thought I would go with a
new chip. I got a P3/1.2GHz chip, and after installing realized the
CUSL2-C would not run with it.

So I got a TUV4X board, since that would run with the P3/1.2 chip, and
would let me go to 1.5GB RAM.

I rebuilt the machine, and found that the chip will not allow me to
boot at any speed other than 600MHz. The TUV4X recognizes the RAM, but
it will not boot at anything but 600MHz. I have the board set for
jumperless, and the choices I get for the chip speed are "manual, 600
900 and 1200". I am under the impression I fried the chip on the
CUSL2-C, or some other way, since the board seems fine.

Is there any reason to think that if I got another P3/1.2GHz chip it
would also not run at rated speed? Seems I know enough about building
computers to screw up nicely.

Any assistance really appreciated.

 

[Mistoffolees]

I had built my computer on an Asus CUSL2-C with a P3/866MHz chip. This
was a great mainboard, but I needed more performance. Medical problems
precluded building a new machine, so I first thought I would go with a
new chip. I got a P3/1.2GHz chip, and after installing realized the
CUSL2-C would not run with it.

So I got a TUV4X board, since that would run with the P3/1.2 chip, and
would let me go to 1.5GB RAM.

I rebuilt the machine, and found that the chip will not allow me to
boot at any speed other than 600MHz. The TUV4X recognizes the RAM, but
it will not boot at anything but 600MHz. I have the board set for
jumperless, and the choices I get for the chip speed are "manual, 600
900 and 1200". I am under the impression I fried the chip on the
CUSL2-C, or some other way, since the board seems fine.

Is there any reason to think that if I got another P3/1.2GHz chip it
would also not run at rated speed? Seems I know enough about building
computers to screw up nicely.

Any assistance really appreciated.

If the apparent CPU speed is off by a simple multiple, such
as one-half, then check that the motherboard is running with
an updated version of the bios. Download it and re-flash the
bios, per instructions in the manual, with the update. This
presumes that the motherboard revision number and bios do
support the CPU in question.

 

[Roland Scheidegger]

I had built my computer on an Asus CUSL2-C with a P3/866MHz chip. This
was a great mainboard, but I needed more performance. Medical problems
precluded building a new machine, so I first thought I would go with a
new chip. I got a P3/1.2GHz chip, and after installing realized the
CUSL2-C would not run with it.

So I got a TUV4X board, since that would run with the P3/1.2 chip, and
would let me go to 1.5GB RAM.

I rebuilt the machine, and found that the chip will not allow me to
boot at any speed other than 600MHz. The TUV4X recognizes the RAM, but
it will not boot at anything but 600MHz. I have the board set for
jumperless, and the choices I get for the chip speed are "manual, 600
900 and 1200". I am under the impression I fried the chip on the
CUSL2-C, or some other way, since the board seems fine.

Since you mentioned 1.5GB ram, do you use 3 modules with 512MB, each
organized as 64Mx4? That'll almost never work, and it could probably
explain why the board would only run at 600Mhz (I'm not sure, but the
board probably tries to run the memory and fsb clock synchronously, so
at 600Mhz you'd have only 66Mhz FSB&mem clock, but at 1200Mhz you'd got
133Mhz). If so try with only 1 module.
It seems a bit odd that a cpu would get damaged in a way that it'll only
run at half its speed.

Roland

 

[Steve Sohn]

Since you mentioned 1.5GB ram, do you use 3 modules with 512MB, each
organized as 64Mx4? That'll almost never work, and it could probably
explain why the board would only run at 600Mhz (I'm not sure, but the
board probably tries to run the memory and fsb clock synchronously, so
at 600Mhz you'd have only 66Mhz FSB&mem clock, but at 1200Mhz you'd got
133Mhz). If so try with only 1 module.
It seems a bit odd that a cpu would get damaged in a way that it'll only
run at half its speed.

Roland

Thank you both for the replies.

Well, believe it or not, I have the board running at 1200MHZ, after
fiddling with the System/SDRAM Frequency Ration - set it to 4/3 - and
it runs at 1200MHZ.

I am intrigued by your comment about three modules of 512MB, which is
what I am running. I have two new Crucial SDRAMs, with a CAS latency
of 2, and another that is generic and from my CUSL2-C board, that is
probably not the same latency. If not three 512MBs, would you
recommend two 512MBs and two 256MBs?

Also, the System CPU Frequency Multiple shows as "Locked"; would that
contribute to my not be able to overclock this CPU?

Thanks very much for the information.

 

[Roland Scheidegger]

Well, believe it or not, I have the board running at 1200MHZ, after
fiddling with the System/SDRAM Frequency Ration - set it to 4/3 - and
it runs at 1200MHZ.

I am intrigued by your comment about three modules of 512MB, which is
what I am running. I have two new Crucial SDRAMs, with a CAS latency
of 2, and another that is generic and from my CUSL2-C board, that is
probably not the same latency. If not three 512MBs, would you
recommend two 512MBs and two 256MBs?

No, usally it's better to reduce the number of modules. If it doesn't
run with 3 modules, it likely won't run with 4 neither. Do you really
need so much ram? Otherwise I'd suggest just tossing out the 3rd generic
dimm and try if things are stable then. I don't think Crucial sells
those crappy modules built with 64Mx4 chips, but I'm not too certain.
If you try with 2 modules and it seems to run stable, you should use a
memory tester such as memtest86+ to see if it's really running stable.
www.memtest.org.

Also, the System CPU Frequency Multiple shows as "Locked"; would that
contribute to my not be able to overclock this CPU?

Yes you cannot change the multiplier of any intel cpu since early P2/P3
days, unless it's an engeneering sample. You should be able to change
the front side bus though, I think pretty much all asus boards can offer
more than just the standard 66/100/133Mhz you apparently could choose
from. Though since your results indicate your ram doesn't even run at
100Mhz, it doesn't really make much sense to try to overclock...

Roland