Cheapest/best AM3 CPU to unlock

[Cheapy]

My Phenom II X3 710 on a Gigabyte MA770T-UD3P unlocked sucessfully to a quad but I havnt run it though prime due to tempertures as the CPU VRM area is meant to run hot and it reommends additional cooling for it.

[shaithis]

Thanks for the info......he finally went with an Asus M4A785TD-V EVO and a 550BE, unlocked to 4 cores, prime stable

[Uriel]

My new Asus M3A78-T whilst a bargain at 51 quid (nice one Scan) failed to unlock in the brief try I gave it.
I just hope a future bios update gets the M3A board up to the same ACC feature level.

BIOS version can be key. On my board the A01 (early 2009, I think) BIOS didn't unlock. A07 (Oct 09) and A09 (Dec 09) both unlock.

Some manufacturers are taking unlocking out of newer BIOS versions. Asus and Gigabyte have incorporated the 'fix' (so ACC works without core unlocking - it's very handy for overclocking Phenom Is), whilst electing to give the consumer the option of unlocking.

MSI also gives the option for ACC with or without unlock but some MSI boards don't have the necessary voltage controls to stabilise CPUs that are a little bit dodgy.

[Firejack]

The voltage on my CPU is a bit weird. At Athlon II X3 425 stock it used a Vcore of 1.320 under load and yet unlocked to a Phenom II X4 B25 it only needs 1.280 . I would of expected it to need more.

Anyhow I'm now overclocked at 3.01GHz which is were I think I'll end this madness. £54 for a 3GHz quad core is quite the bargain

Not wanting to post hi-jack but what memory/motherboard have been used for these systems?

I'm using 4GB Corsair DDR2 (TWIN2X4096-6400C5) memory and an Asus M4A785D-M Pro motherboard. Using BIOS revision 0704 which is the newest on the Asus website.

[Terbinator]

So all you guys are using DDR2 ?

[shaithis]

So all you guys are using DDR2 ?

The system I speced for the guy at work had DDR3

[Uriel]

Most of the Athlon IIs will undervolt from stock quite happily.

I'm using DDR2 but this X2 5000+ is AM2+ so the IMC doesn't control DDR3. I've seen plenty of people unlocking AM3 chips with DDR3 though.

[Nanek]

I'm one of the unlucky ones with a 550 BE. Unlocked it, booted fine, ran prime for about 4-5 hours without an issue, however, when gaming it kept crashing after about 20~ minutes. Have not had any issues as a dual core so i'll just stick to a 3.8ghz dual core I suppose :>

[scaryjim]

I unlocked my Sempy 140 on DDR3 (1x2GB) with an ASUS M4A785G-TD-M EVO (or whatever it's ridiculously complex name is ). But as Uriel says, the X2 5000+ is socket AM2+, so DDR2 only for those...

[Terbinator]

Bugger, thought i was onto something then why mine wont unlock, other than the fact that it wont Maybe them new six-core ones will be AM3, if not they'll push the prices of the X2/3/4's down to a decent level

[scaryjim]

What're you trying to unlock, a Sempy 140?

Could just have been unlucky with the chip - after all, there must be a reason they're not selling them as Athlon X2s outright. Mine started exhibiting instability after a couple of weeks running unlocked @ 1.05V (-0.3v from stock) and I've taken it back to a single core as I don't really need the second core for playing DVDs and watching iPlayer

[Terbinator]

Yeah its a Sempron - would of been nice to have the extra 'oomph though, its only going to be used for Office and browsing and it seems to partial to a mild overclock ^_^

By the way how are you undervolting, mine only offers the option to go to auto no matter how much i mash "-"

[scaryjim]

You're on the mATX Evo, right? I'll have a look tomorrow and let you know!

[Terbinator]

You're on the mATX Evo, right? I'll have a look tomorrow and let you know!

Yeah, same as you!

[DanceswithUnix]

Bugger, thought i was onto something then why mine wont unlock, other than the fact that it wont Maybe them new six-core ones will be AM3, if not they'll push the prices of the X2/3/4's down to a decent level

Six cores, hmm lets hope they release some of those locked down to dual core as well eh?

[Keyboard]

I bought a Phenom II x2 550BE and an ASRock M3A790GMH/128M just before Christmas. I updated the BIOS to the latest v1.3 and unlocked to get 4 cores (didn't even try with the BIOS that the mobo shipped with). I ran various burn-in tests for at least an hour and everything was stable.

With unlocked cores, it doesn't seem possible to see the core temepratures any more, but the CPU package temperature is still reported. With the stock cooler that came with the CPU, the temperature didn't get over 60 deg.c. when running the burn-in tests (ambient ~23 deg.c.). The core temps seem to be within 5 deg.c. of the package temps at the most. But I'm planning on updating the cooler before running SETI@home with the unlocked CPU !

This isn't the cheapest mobo/CPU combination that may unlock, but it worked for me, and if it hadn't, I'd still been left with a decent set-up. My philosophy was to build something that met my needs and take any unlock as a bonus