Unlocking Cores on an AMD Processor

[alanbjames]

Im using an AMD FX4100 Quad Core and on this site it states that it has 4 other cores that can become unlocked....

http://www.legitreviews.com/amd-fx-4...or-review_1766


This is the board im using...
http://www.msi.com/product/mb/990FXA.../?div=Overview

Anyone have any ideas?

check your bios for cpu core control

All 890 chipset boards can do it so I assume ( maybe incorrectly) that 990 boards being the better chipset can also. You may need to update bios

your motherboard apparently does support it

---------- Post added at 09:34 ---------- Previous post was at 09:28 ----------

unlock cpu core under overclocking. It is in the manual lol lol

Originally Posted by heero_yuy

I would hazard a guess that this is the higher 8 core spec processsor that the other four cores failed to perform in so is marked down in price. The dud cores are probably disabled by a bond wire option.

The other cores may well work but not be reliable at the clock rate of the working ones and if they're bonded out will not be accessable.

This is quite common, decades ago I remember the 2756 EPROM that was basically the working half of the 2716 EPROM but at a much lower price. IIRC there was a x86 CPU that had a dud co-processor so was marked as an SX type.

For the real old timers remember the undocumented orthogonal register set in the Z80 CPU?

unlockable in Bios AMD did it for a while allowing easy unlock in code. Whether or not the cores will work at the frequency remains to be seen but they might just not have made the tolerance and may run fine

Originally Posted by heero_yuy

Interesting to debate whether running all 8 cores at a lower clock out-perform 4 cores at full speed.

Guess it depends on how well the OS metes out the tasks.

and what tasks the user performs

[AbyssUnderground]

Make sure the motherboard can handle the power of all the cores, I did this to one that couldn't and it broke

Originally Posted by AbyssUnderground

Make sure the motherboard can handle the power of all the cores, I did this to one that couldn't and it broke

the vcore is decided by the bios did this change when you unlocked the cores? If the boards support 8 core cpus and you unlock a 4 core to an 8 core I do not see how it is the power that would have caused this unless it set itself stupid high like overvolting a full volt or something

[AbyssUnderground]

Basically I got a Phenom II dual core but it was a quad core locked down to a dual core. The motherboard I got was only capable of a max of 85w CPU's, the now unlocked quad core was 105w, so when loaded up to 100% usage, it burnt something out because of the extra power draw. I suffered crashing all the time not long after I unlocked it. I tried swapping the memory out but that made no difference. After looking into it I found the power requirements thing and assumed that was what caused it.

Originally Posted by AbyssUnderground

Basically I got a Phenom II dual core but it was a quad core locked down to a dual core. The motherboard I got was only capable of a max of 85w CPU's, the now unlocked quad core was 105w, so when loaded up to 100% usage, it burnt something out because of the extra power draw. I suffered crashing all the time not long after I unlocked it. I tried swapping the memory out but that made no difference. After looking into it I found the power requirements thing and assumed that was what caused it.

oh right I understand now

[damien c]

Originally Posted by AbyssUnderground

Basically I got a Phenom II dual core but it was a quad core locked down to a dual core. The motherboard I got was only capable of a max of 85w CPU's, the now unlocked quad core was 105w, so when loaded up to 100% usage, it burnt something out because of the extra power draw. I suffered crashing all the time not long after I unlocked it. I tried swapping the memory out but that made no difference. After looking into it I found the power requirements thing and assumed that was what caused it.

That is still happening these days with the AMD chips that run at 4.7Ghz and 5.0Ghz, if you get a bored that cannot handle the power draw through the VRMS and bang the boards, burn out.