Phenom II x2 555 or Phenom II x4 B55

[Bakersoft]

There was a time when AMD released a Phenom II x2 555 as a result of a batch of 955's that were 'bad'. Instead of tossing them, they sold them with 2 cores disabled as a dual-core. Then after demand for the duals increased, they continued disabling 2 cores from a 955 to move product as sales on the cheaper dual-core were greater. I have such a processor that I acquired from eBay rather cheap. "The Phenom II X2 is nothing more than a Phenom II X4 with two cores disabled" as Anandtech claims.

Exciting! Well I got myself an ASUS M5A78L-M LX PLUS mobo and used the unlock function for the disabled 2 cores to utilize all 4. Here's what has changed on me so far...

1. I no longer have temp readings in hwmoniter for any of the 4 cores.

2. I get random errors when installing things and such.

3. My WEI score improved more than half a point. (From 6.6 to 7.3)

4. Game performance hasn't really changed. (I need to run more tests with the old settings of the X2 to show proof, I know)

My question is... How do I know if I got an X2 555 that should have been left as a dual-core. Or is what I got the best I should hope for? Gaming performance aside, the computer is a bit snappier; I do realize. What kind of test should I run besides Prime95 to find out if this CPU at the 3.2Ghz configuration is good enough to call it done? (Since I get no temp readings I do not want to run Prime95 too long) My real concern is, my buddy is considering buying this build from me... And I want to set himself up with a solid computer that isn't going to be a bother, on the cheap. I'd like a LinusTech employee to give me a solid response, as I trust their opinion. Unless you, as the reader, has dealt with unlocking cores in the past.

Case Rosewill FBM-02

Mobo ASUS M5A78L-M LX PLUS

CPU Phenom II X4 B55 (X2 555) @3.2Ghz

RAM Kingston 2x4GB 1333Mhz

HDD Seagate 2TB 7200

GPU GeForce GTX 570

PSU Cooler Master 600W

Selling at $350 for a dedicated media PC and WoW machine for daughter. Thanks for the read!

[Opcode]

Try using other software such as ADIA64 or CoreTemp. Hopefully one will do the trick. Its hard to leave it unlocked when you don't know how hot it's getting. Other than that if it runs Prime95 for a few hours without fail then the extra two cores are good. You're just stuck in a pickle with temperature readings.

[Bakersoft]

Thanks for your help! CoreTemp showed the same as hwmoniter, but AIDA64 shows the (I think) proper temps. Only a few minutes in and I've got 53C on the core. Sounds bad, but it's the stock fan. Also CPU-Z shows it at 160W TDP if that's any news for you. At the end of me typing this I've got 55C on the CPU according to AIDA64. Seems to be stabilized at this temp, albeit 1 or 2 more degrees. Any other information I should acquire about my unique CPU?

[Opcode]

Thanks for your help! CoreTemp showed the same as hwmoniter, but AIDA64 shows the (I think) proper temps. Only a few minutes in and I've got 53C on the core. Sounds bad, but it's the stock fan. Also CPU-Z shows it at 160W TDP if that's any news for you. At the end of me typing this I've got 55C on the CPU according to AIDA64. Seems to be stabilized at this temp, albeit 1 or 2 more degrees. Any other information I should acquire about my unique CPU?

In AIDA64 look at the CPU temperature as AMD doesn't distribute senors to each core. 53C isn't too bad for a stock cooler as long as it stays under 62C. The Phenom II x2 555 is a 80w TDP chip tho once you unlock the two extra cores its TDP becomes 125w. I wouldn't recommend overclocking too much on the board that's in that machine. The only safe thing to do for added performance gains is to keep it unlocked at stock clocks. Also what volts are you running it at? You could try dropping volts down manually in the BIOS and stress testing it again a few times to lower its vcore. That would help reduce its temperatures while prolonging the lifespan of the chip.

[Amrat]

I have the same CPU unlocked to 4 cores. You won't be able to check the core temperatures in the unlocked state. Whatever temps you see through any software ( When unlocked ) is not the real temperature of the CPU, the real ones are always little less than that.

[Bakersoft]

I'm getting strange "Floating Point Exception" errors when I install games and programs. But runs just fine when they get done installing. Is this CPU related?

[Bakersoft]

Bump please.

I reinstalled windows thinking it could be software based. I've installed a few games and once its installed it runs without issues. But during the installation I get floating errors. I hit ok, then it continues for only a few seconds and the error pops up again.

It does not do this with the CPU left as a dual-core. What should I do? Install things as an X2 555, then switch BIOS to the X4 B55 to play games?

[sgloux3470]

If you're getting errors, you should probably leave it in dual core mode.  You could also try downclocking it a bit though too I suppose.  

[Opcode]

Bump please.

I reinstalled windows thinking it could be software based. I've installed a few games and once its installed it runs without issues. But during the installation I get floating errors. I hit ok, then it continues for only a few seconds and the error pops up again.

It does not do this with the CPU left as a dual-core. What should I do? Install things as an X2 555, then switch BIOS to the X4 B55 to play games?

If you're getting errors either one of the locked cores are bad or they are starving for power.