Reinstalling os if changing cpu

[fantomau]

If I was to just change my cpu w/o changing mobos, Would I need to re-install xp?

 

[AMDXP]

Not unless you have problems, which I doubt.

 

[fantomau]

Ok thanx, Thats what I thought, Just wanted to clarify.

 

[searaider]

No way, just changed an E8400 for an E8600 and no need to reinstall os

 

[tlc4tvm]

That somewhat depends on the processor...

If it's a single core non hyper treaded like a older amd and your going dual core....

Then you might need to reinstall to get multiprocessor aware O/S but more than likely just plug and go.

 

[tlc4tvm]

That somewhat depends on the processor...

If it's a single core non hyper treaded like a older amd and your going dual core....

Then you might need to reinstall to get multiprocessor aware O/S but more than likely just plug and go.

 

[fantomau]

That somewhat depends on the processor...

If it's a single core non hyper treaded like a older amd and your going dual core....

Then you might need to reinstall to get multiprocessor aware O/S but more than likely just plug and go.

Read my sig.

 

[gwai lo]

Your sig doesn't include what chip you upgraded from or to.

 

[fantomau]

FROM a E8400 (in my sig) to a Q9650

 

[BinarySynapse]

CPU: Intel E8400 C2D @ 3.6Ghz
Case: Lian Li PC-A70b w/ W-75 Side Panel

FROM a E8400 (in my sig) to a Q9650

His point was that it's not clear if you upgraded to that CPU, or are planning on upgrading from that CPU. Which is meaningless; if you'd already upgraded, then this thread would have taken a different form.

Since you already have a multicore CPU, Windows already has the multiprocessor HAL installed and you won't have to reload another HAL or the entire OS to enable that support.


EDIT: took too long to hit submit...

 

[PGHammer]

No way, just changed an E8400 for an E8600 and no need to reinstall os

Generally, if you're ONLY changing the CPU, the only time to change operating systems is if you're moving from 32-bit to 64-bit (and in that case, all I can say is "What kept you?").

 

[PGHammer]

His point was that it's not clear if you upgraded to that CPU, or are planning on upgrading from that CPU. Which is meaningless; if you'd already upgraded, then this thread would have taken a different form.

Since you already have a multicore CPU, Windows already has the multiprocessor HAL installed and you won't have to reload another HAL or the entire OS to enable that support.


EDIT: took too long to hit submit...

The following CPUs all normally use the 32-bit ACPI multiprocessor HAL:

All Northwood-C Pentium 4 CPUs (without exception)
The Pentium 4 Northwood-B 3.06 GHz
All Prescott Pentium 4 CPUs in S478 (without exception)
(These Netburst architecture CPUs all support HyperThreading Technology.)

The Core Duo (not Core 2 Duo) in LGA775 supports the 32-bit ACPI multiprocessor HAL, but not a 64-bit HAL.

Surprisingly, current-model single-core *Celerons* actually support the 32-bit and 64-bit ACPI HALs (either single-core or multicore), despite having only one active core.

Celeron DC and Pentium DC CPUs support the 32-bit and 64-bit MP HALs directly, but not in VMs, as they do not support VT.

Core2Duo and Core2Quad CPUs (with limited exceptions) support both 32-bit and 64-bit MP HALs and support VT modes (however, some C2Ds and even some C2Qs don't support VT modes), so there may be some VM reconfiguration needed if upgrading from a CPU that doesn't support VT to one that does.

 

[BinarySynapse]

The following CPUs all normally use the 32-bit ACPI multiprocessor HAL:

All Northwood-C Pentium 4 CPUs (without exception)
The Pentium 4 Northwood-B 3.06 GHz
All Prescott Pentium 4 CPUs in S478 (without exception)
(These Netburst architecture CPUs all support HyperThreading Technology.)

The Core Duo (not Core 2 Duo) in LGA775 supports the 32-bit ACPI multiprocessor HAL, but not a 64-bit HAL.

Surprisingly, current-model single-core *Celerons* actually support the 32-bit and 64-bit ACPI HALs (either single-core or multicore), despite having only one active core.

Celeron DC and Pentium DC CPUs support the 32-bit and 64-bit MP HALs directly, but not in VMs, as they do not support VT.

Core2Duo and Core2Quad CPUs (with limited exceptions) support both 32-bit and 64-bit MP HALs and support VT modes (however, some C2Ds and even some C2Qs don't support VT modes), so there may be some VM reconfiguration needed if upgrading from a CPU that doesn't support VT to one that does.

Which agrees with what I said. Those are all multicore (or appear to the OS as such) processors. Even the single-core Celerons based on Core technology are just disabled dual-cores where the OS can still see the second core listed, but can't access it.

Earlier mobile Pentium DC chips are just rebranded Core Duo's and this don't support 64bit OS's.

 

[On the Lam]

Old thread, but if I'm on a Gigabyte EP45-UD3L with an e4300 cpu, and later I move to a newer 45nm cpu like a Q9550, will I need to reinstall OS?

 

[Nenu]

No you should be fine too.
The problem occurs if you have the single CPU, uniprocessor HAL (Hardware Abstraction Layer) installed already.
There are ways to get the multiprocessor HAL installed if you upgrade to a multicore CPU but they arent straight forward.

MS's official stance is to re-install windows when you require a new HAL that doesnt automatically install.
A similar thing occurs if you disable certain power saving features of the CPU in the CMOS (related to using idle states).
Once you make the change in the CMOS, a new HAL is installed.
Reverting the setting back in the CMOS does not put the original HAL back so you have to manually change it or re-install to get it back.

In case anyone finds this useful...
I found out this morning that Windows 7 makes it much easier to change your motherboard etc.
I was running Windows 7 x86 on an Athlon XP, Abit AN7 motherboard and changed to an Athlon64, Gigabyte K8NS motherboard.
(I didnt uninstall the previous drivers before changing motherboard)
Windows booted without issue, the new hardware was detected and then asked to reboot.
From then on it worked great.
Hopefully it will install the correct HAL when the CPU is changed from single to multicore or back to single, as well.

 

[On the Lam]

Thanks for your answer.