PII 720 Quad Core !! (not a typo)

ecat · 17 Feb 2009 at 19:51

I've not seen this done before so thought I'd share...

That's strange...

That's very strange...

But true, four cores as near as I can tell. Manually setting the CPU affinity while running SuperPI I can stress each core individually, I don't know what other tests I can perform to prove its quad corelyness.

There is of course a down side, even at 1GHz Prime95 on all cores fails, but with another chip, well, who knows ?

And how do we unlock this 4th core ? Simple. On an Asus M3A79-T running the 703 bios you enable ACC. That's it

Oh well, so I really do have a quad cripple, or is this just some SW anomaly ? Still @ 3.8GHz this cripple rocks

Cyber-Mav · 17 Feb 2009 at 19:53

what does task manager show?

ecat · 17 Feb 2009 at 19:58

Task manager shows 4 cores too, as does Prime95 and everything else I've tried

Mul · 17 Feb 2009 at 20:07

That's quite impressive.

Have you tried running three of four cores operate at 3.8GHz and the fourth at a reduced frequency, as I understand you can set separate clock speeds for each core in AMD Overdrive with Phenoms?

ecat · 17 Feb 2009 at 20:12

Even at 1GHz I get failures so not much point investigating further. More of a curiosity, for my little cpu at least. The memory controller is common to all cores I think, so there's not much point in playing with bus speed either.

It does boot at full speed, just means the bad core is not stressed during start up I guess. Here's the validation page

http://valid.canardpc.com/show_oc.php?id=510443

The other down side is that I can't use ACC, reports vary but some are getting an extra 200 to 300MHz with it enabled. It would be nice to hit the 4G mark.

Hello to the guys on Xtreme, I'm still waiting for my authorisation e-mail

humm, I wonder if the same trick will work on the rumoured dual-cores ?

cavemanoc · 18 Feb 2009 at 20:18

This is good news though - if AMD decide to try to shift the numbers they may well rebin fully functioning X4s in the X3 pile - back to the good old days for the 6800LE and x800GTO with the magically opening pipes

Have you tried downclocking the faulty core via Overdrive to see if you can get anything useful out of it - might be fun to have it as a dedicated Skype/Teamspeak core while playing

Mul · 23 Feb 2009 at 11:00

http://www.xtremesystems.org/forums/showthread.php?t=218811

Apologies for bumping this thread, but it would appear that someone else has managed the same by setting ACC to Auto but with an X3 710. They're certainly weak cores but it's interesting regardless.

didgemaster · 23 Feb 2009 at 20:02

same reported on toms hardware - I imagine its the same Korean site

http://www.tomshardware.co.uk/amd-phenom-cpu,news-30376.html

paradigm · 27 Feb 2009 at 11:55

ignore, wrong thread

paradigm · 27 Feb 2009 at 11:56

OMG doube fail post

DavyBoy · 27 Feb 2009 at 16:50

That is quite interesting.. does this work with all X3 processors?

David230 · 27 Feb 2009 at 19:29

I was going to try this with my 720be on a new Gigabyte 790FX AM3 mobo. This board boasts the ACC feature but I cannot find anything in the bios about acc. Also I have tried different versions of overdrive and they all display the ACC settings as disabled (greyed out).

Does anyone know about setting up this feature on the AM3 board?

ecat · 28 Feb 2009 at 13:15

DavyBoy said:
That is quite interesting.. does this work with all X3 processors?

It's a lottery I'm afraid. Some X3's don't unlock. Of the X3's that do unlock some, like me

, have a 4th core incapable of even 1GHz, others have better luck reaching full rated speed or even beyond...
http://www.xtremesystems.org/forums/showpost.php?p=3675438&postcount=11

David230 said:
I was going to try this with my 720be on a new Gigabyte 790FX AM3 mobo. This board boasts the ACC feature but I cannot find anything in the bios about acc. Also I have tried different versions of overdrive and they all display the ACC settings as disabled (greyed out).

Does anyone know about setting up this feature on the AM3 board?

The PII processors should not need ACC, it looks like some mb manufacturers, but not all, are disabling/removing the ACC feature when a PII is detected.

TheMorningStar · 28 Feb 2009 at 15:33

i have acc on my asus m3a79t and all it does is fail to boot when i switch it on. amazing feature i know. im not sure what all these people are getting out of enableing it on Phenom II's....

Final8y · 28 Feb 2009 at 16:44

WARNING to all DK 790FXB-M2RS(H) users regarding BETA BIOS 02/24:

Do not flash this beta unless you have AMD 7xx CPU:
Major Reasons of Change:
The BIOS added 65nm ACC code for AMD Phenom II 710 / 720 CPUs(45nm) only.

It looks like ACC is still used on PII in some form.

deuse · 28 Feb 2009 at 17:28

All I can say is DONT update your bios
http://www.techpowerup.com/86459/Phenom_II_X3_Demand_Skyrockets_Post_Core-Unlock_Mod.html

http://www.techpowerup.com/86442/Ph...ssfully_Unlocks_Fourth_Core_AMD_Steps_In.html

loads more about it on the net

NightmareXX · 28 Feb 2009 at 17:37

Final8y said:
It looks like ACC is still used on PII in some form.

If I'm thinking correctly, ACC has been built in to the new PII chips so it isn't needed at all.

gareth170 · 28 Feb 2009 at 17:51

Final8y said:
It looks like ACC is still used on PII in some form.

i think it means it disable's the motherboard ACC when using the 710/720 so u can't enable the forth core.

iMacMart · 1 Mar 2009 at 12:28

Tried this with my board and chip, wouldn't boot had to reset the BIOS...

Worth a shot I suppose......

paradigm · 1 Mar 2009 at 12:30

Mine won't unlock either, oh well