Should I Upgrade From 2.4G CPU to 3G CPU?

[Jethro]

My MB has a front-side-bus of 400/533 Mhz. If I put in a CPU with a
800 Mhz FSB that wouldn't cause any problems would it? It wouldn't be
operating at it's full capability, but would that cause other timing
problems? I would think it would be like memory, where you can use
faster memory, but not slower.

I would like to upgrade to a faster 3.0 Gig CPU from my existing 2.4
Gig and there are not many 478 pin CPUs left to choose from.

 

[Paul]

My MB has a front-side-bus of 400/533 Mhz. If I put in a CPU with a
800 Mhz FSB that wouldn't cause any problems would it? It wouldn't be
operating at it's full capability, but would that cause other timing
problems? I would think it would be like memory, where you can use
faster memory, but not slower.

I would like to upgrade to a faster 3.0 Gig CPU from my existing 2.4
Gig and there are not many 478 pin CPUs left to choose from.

The multiplier is locked, so the core of the processor will not
run at full speed. Some motherboards with 845PE chipset, can actually
overclock to the FSB800 level (just barely), so depending on the
chipset and motherboard design, I suppose you could get there via
overclocking. But the 845PE would only support one DIMM at DDR400,
which is a weakness of the scheme - probably the perfect solution
for someone still running Win98, with its limits on usable memory.

You could jump ahead a generation.

ASUS P5PE-VM Socket T (LGA 775) Intel 865G
http://www.newegg.com/Product/Product.asp?Item=N82E16813131029

Core2 Duo of your choice (note: runs at stock - no overclock with P5PE-VM)

That product has an AGP 8X slot (so your vid card should support
1.5V, to make this upgrade possible). The board uses DDR memory,
and a matched pair are recommended.

The 865G chipset is only designed by Intel to do FSB800, but it runs
overclocked to FSB1066 by Asus. That means you should not expect
the P5PE-VM to overclock further. You install a
Core2 Duo processor and it runs at *stock* for as long as
you own the board. Some day, when you want to buy a fancy
PCI Express video card, you ditch this motherboard, buy the
new PCI Express video card, a pair of DDR2 DIMMs, and you
upgrade your motherboard to something decent. You can reuse
your Core2 Duo.

There are similar upgrader motherboards on the Asrock site.
Again, the chipsets used (typically VIA) are already overclocked, to
reach the FSB1066 level, so those boards wouldn't overclock worth
a damn either. If you want to overclock, an Intel 965 or
975 based motherboard would be a better choice, but then
you'd be ditching AGP and DDR, and the upgrade would be
more expensive..

Basically, the P5PE-VM is a "processor cost + $55" upgrade for
legacy (non-overclocking) users. Only supports two sticks
of DDR, so when Vista arrives, you'd either switch to
2x1GB DDR PC3200 for about $200 more, or make your
transition to PCI Express and a more modern motherboard
(makes more sense at that point).

While there are cheap older Intel processors in the LGA775
form, they would not be my first choice.

You could also try overclocking your current processor. That
is a cheap upgrade, but a tiny one.

I haven't mentioned AMD, because I believe you are already
familiar with the options available there, based on your
previous posts.

Paul

 

[kony]

My MB has a front-side-bus of 400/533 Mhz. If I put in a CPU with a
800 Mhz FSB that wouldn't cause any problems would it? It wouldn't be
operating at it's full capability, but would that cause other timing
problems? I would think it would be like memory, where you can use
faster memory, but not slower.

If your board can run it, it will do so only at the max FSB
speed the board supports (unless you can and choose to
overclock it, and it's not likely you can o'c it that far).

The CPU has a locked multiplier. Multi x FSB = total speed.
See the problem? Using a 3GHz CPU with QDR800 FSB spec may
result in only 2GHz CPU operation.

I would like to upgrade to a faster 3.0 Gig CPU from my existing 2.4
Gig and there are not many 478 pin CPUs left to choose from.

The slower FSB and memory speed would bottleneck this
upgrade even if it would work, combined with the aging high
heat architecture of the P4, it wouldn't be much of an
upgrade if possible (even taking a very isolated look at
only the CPU, ignoring other performance variables, that
alone is only 25% increase in clockspeed using
same//similar-enough core design). If overclocking would
be acceptible you might o'c the present CPU, else it's time
to switch motherboards.

 

[CBFalconer]

My MB has a front-side-bus of 400/533 Mhz. If I put in a CPU with
a 800 Mhz FSB that wouldn't cause any problems would it? It
wouldn't be operating at it's full capability, but would that
cause other timing problems? I would think it would be like
memory, where you can use faster memory, but not slower.

I would like to upgrade to a faster 3.0 Gig CPU from my existing
2.4 Gig and there are not many 478 pin CPUs left to choose from.

Why? You won't even notice a 25% speedup. Your memory may not
keep up.

 

[meow2222]

Jethro wrote:

Why? You won't even notice a 25% speedup.

Fsb has far more effect IME on system speed than CPU speed. However if
the mobo doesnt do 800 fsb, putting an 800fsb cpu in will at best give
you a cpu running at near half its rated speed, ie a large downgrade.

As usual I'd question the need in the first place, I've not found these
478s lacking in performance. I'm using one now. Have you done all the
usual stuff and shut down unwanted background processes, and gone
through the OS with Autoruns to shutdown all the bits you'll never use
there too. Then look at your apps, the performance difference between
well written and mediocrely written apps can be huge.


NT

 

[paulmd]

My MB has a front-side-bus of 400/533 Mhz. If I put in a CPU with a
800 Mhz FSB that wouldn't cause any problems would it? It wouldn't be
operating at it's full capability, but would that cause other timing
problems? I would think it would be like memory, where you can use
faster memory, but not slower.

I would like to upgrade to a faster 3.0 Gig CPU from my existing 2.4
Gig and there are not many 478 pin CPUs left to choose from.

To summarise what others have said. "No, leave it alone, you won't see
a performance increase and/or may have problems."

 

[DaveW]

The motherboard's BIOS would not recognize the 800 MHz FSB CPU. No can do.

 

[Jethro]

My MB has a front-side-bus of 400/533 Mhz. If I put in a CPU with a
800 Mhz FSB that wouldn't cause any problems would it? It wouldn't be
operating at it's full capability, but would that cause other timing
problems? I would think it would be like memory, where you can use
faster memory, but not slower.

I would like to upgrade to a faster 3.0 Gig CPU from my existing 2.4
Gig and there are not many 478 pin CPUs left to choose from.

Thanks all for your comments and such.

HNY

Jethro