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Try as I might, I have not been able to find anything concerning the future road map for 686 PAE support. I know that 686 PAE is supported in Stretch but am wondering for how much longer Debian will continue 686 PAE support.

PAE is a kernel feature that can be turned on or off at users will. Debian cannot forbid you from turning it on.

^ i don't think the question was meant like that.

i'm using debian stable on a 32 bit machine with pae support.
this basically means: only even older 32bit machines do NOT have pae support, and there's indeed fewer and fewer linux distros supporting them.

although i'm pretty sure debian is NOT one of those.

but some distros are phasing out 32 bit support completely (even for machines with pae support).

again i'm pretty sure debian is NOT one of those.


it's a valid question; i'd have to change server hardware if that ever happened...

debiman wrote:
it's a valid question; i'd have to change server hardware if that ever happened...

Yeah, that's pretty much where I was coming from. I am running a 32 bit system that has a Core2Duo processor (with PAE). Really not eager to spend the money to upgrade to a 64 bit system. Of course I suppose I never have to update the system as long as I am never concerned with security updates. I know that with LTS I should be okay for the next 2 or 3 years. After that who knows. I imagine that eventually Debian will phase out support for 686 PAE processors. Other distros have already begun doing so.

It'll be interesting to see how long the 32-bit stuff stays around. The hardware won't last forever. About once a year I go through the exercise of rebuilding an old server to troubleshoot and replace a failed drive or 2. There's only 3 of those systems left in my environment now.

ticojohn wrote:

debiman wrote:
it's a valid question; i'd have to change server hardware if that ever happened...

Yeah, that's pretty much where I was coming from. I am running a 32 bit system that has a Core2Duo processor (with PAE). Really not eager to spend the money to upgrade to a 64 bit system. Of course I suppose I never have to update the system as long as I am never concerned with security updates. I know that with LTS I should be okay for the next 2 or 3 years. After that who knows. I imagine that eventually Debian will phase out support for 686 PAE processors. Other distros have already begun doing so.

Core 2 Duo is a 64-bit processor, what money are you going to spend to upgrade? 64-bit Debian is free.

Segfault wrote: Core 2 Duo is a 64-bit processor, what money are you going to spend to upgrade? 64-bit Debian is free.

The Core2Duo that I have, an E6750, has 32 data bits and 36 address bits. Not sure how that makes it a 64 bit processor, other than it supports PAE. And NO, 64 bit Debian will NOT work on this processor. I tried!

Later Core 2 processors, such as the E8400 do have 64 bit instruction set. Don't know if they have physical 64 bit addressing. I probably should have been more specific in my post.

ticojohn wrote:

Segfault wrote: Core 2 Duo is a 64-bit processor, what money are you going to spend to upgrade? 64-bit Debian is free.

The Core2Duo that I have, an E6750, has 32 data bits and 36 address bits. Not sure how that makes it a 64 bit processor, other than it supports PAE. And NO, 64 bit Debian will NOT work on this processor. I tried!

Yes, the Core 2 Duo has 64 bit instruction set but doesn't have physical 64 bit addressing. I probably should have been more specific in my post.

UPDATE: Well, I have just read a number of posts indicating that MAYBE I should be able to run 64 bit software, eg amd64, on this processor. I tried to run 64 bit jessie and it failed. Might it be for lack or ram (limited to 2 MB), or maybe the MMU on the motherboard, or maybe the BIOS? Don't know. Perhaps I could get a LGA775 motherboard that supports 8 GB of ram and see what happens. If it would work, I could use my existing processor and save the bucks for a new 64 bit processor.

ticojohn wrote: And NO, 64 bit Debian will NOT work on this processor. I tried!

I consider this BS, you probably tried IA-64 Debian which definitely does not work on this processor.

ticojohn wrote:The Core2Duo that I have, an E6750, has 32 data bits and 36 address bits. Not sure how that makes it a 64 bit processor, other than it supports PAE. And NO, 64 bit Debian will NOT work on this processor. I tried!

this sort of BS has been happening back in the days when 64bit was the latest thing.
it's not so long ago when you think about it.

Segfault wrote:

ticojohn wrote: And NO, 64 bit Debian will NOT work on this processor. I tried!

I consider this BS, you probably tried IA-64 Debian which definitely does not work on this processor.

Sorry, but I tried amd64. But I am willing to try again. And I don't BS

Well, then try again. There is no such thing as 32 bit Core 2 processor.

from http://ark.intel.com/products/30784/Int ... uote]E6750 Instruction Set 64-bit[/quote]

Segfault wrote:Well, then try again. There is no such thing as 32 bit Core 2 processor.

I am in the process of downloading debian-live-8.7.1-amd64-xfce-desktop.iso . Hope I can install to an 8GB USB stick (using dd). If not, I have a USB HDD, that was used for backups, that I could burn to. Will post results.

Okay. Here is what I did:
1. Downloaded debian-live-8.7.1-amd64-xfce-desktop.iso
2. Verified MD5sum
3. Copied file to 8GB USB stick using dd
4. Booted machine and went in to BIOS
5. Verified that the USB stick was recognized as a bootable system and selected the device to boot first
6. Boot hangs. No messages.

So, the problem may be that since the BIOS recognizes a maximum of 4 GB, and the MMU also can only handle 4 GB, perhaps there is some incompatibility with amd64. Don't know, but this verifies my earlier statement that I tried and it didn't work. No BS. Don't know if a LGA775 socket motherboard capable of handling 8 GB would work or not. If anybody out there has a LGA775 socket motherboard, with a Core2Duo, running amd64 I would love to hear from them.

CRAP! I am so dumb. Tried to boot the USB on my 64 bit Intel NUC aand it didn't work. Tried in legacy mode. Wasn't even recognized. WTF ? Went back to my desktop and looked at the USB. I had it formatted, for earlier use, as FAT 32. That may a good reason for not working. Will format as ext4 and try again.

ticojohn wrote:CRAP! I am so dumb. Tried to boot the USB on my 64 bit Intel NUC aand it didn't work. Tried in legacy mode. Wasn't even recognized. WTF ? Went back to my desktop and looked at the USB. I had it formatted, for earlier use, as FAT 32. That may a good reason for not working. Will format as ext4 and try again.

You do not need to format the stick, everything on it will be overwritten by ISO image, including the partition table and the filesystem.

I have a Pentium 4 which runs 64bit Debian. However, due to a motherboard limitation, I can only have a maximum of 2GB RAM.

With older CPUs, the motherboard chipset controlled the RAM limits. On modern Intel i3, i5 & i7 CPUs, the CPU controls the limit. PAE was introduced on the Pentium Pro in 1995. If you're unable to access more than 3.2GB of RAM, then your motherboard could need replacing but not necessarily the CPU. It is possible, with a Core 2 Duo, that the motherboard has a 32bit chipset which means PAE is a moot point. I had a Dell Precision M90 laptop which was designed like that.

ticojohn wrote:CRAP! I am so dumb.

I'm glad you found the source of the problem.

Okay. Started over. Used Gparted to format the USB stick as ext4 (it originally was used for other things and was FAT32 - dumb). Copied the iso again using dd. Still doesn't work. I notice that even though the BIOS recognizes the USB as a bootable device, when I look at the USB with Gparted the device is not marked as bootable and the system type is unrecognized. Looks like this may be operator error. I tried to boot the USB on my Intel NUC and it doesn't even recognize the USB. I would burn a CD but don't have any blanks available. Here is the dd command I used: Any helpful suggestions ?