The truth about the Phenom TLB bug...

[Epsilon84]

Straight from the horses mouth...

http://www.techreport.com/discussions.x/13724

For those hoping/thinking the BIOS fix improves performance by 10%, it's actually the opposite. You will get a 10% performance penalty from the BIOS fix, but it guarantees stability.

To recap, the erratum is a chip-level issue involving the TLB logic for the L3 cache that can cause system hangs in specific circumstances. AMD has a fix for the problem in the works, but it degrades performance. AMD has stated publicly that the workaround can lower performance by as much as 10%, although one source characterized the performance hit to TR as 10-20%.

Saucier clarified the exact nature of the workaround for the erratum that AMD has provided to motherboard makers and PC manufacturers. The fix comes in the form of a BIOS update, and this BIOS patch includes an update to the CPU microcode. This update disables the portion of the chip's TLB logic that is problematic. Saucier noted that the L3 cache "still works" with this logic disabled, and he said AMD has no plans to implement the fix for existing chips in a different way.

Also, it appears retail Phenoms are actually slower than the reviewed samples, with a 1.8GHz NB/L3 cache as opposed to the 2GHz NB/L3 as used in reviews.

We don't yet have a BIOS with the workaround to test, but we've already discovered that our Phenom review overstates the performance of the 2.3GHz Phenom. We tested at a 2.3GHz core clock with a 2.0GHz north bridge clock, because AMD told us those speeds were representative of the Phenom 9600. Our production samples of the Phenom 9500 and 9600, however, have north bridge clocks of 1.8GHz. We've already confirmed lower scores in some benchmarks.

Given everything we've learned in the past few days, our review clearly overstates Phenom 9600 performance, as do (more likely than not) other reviews of the product. We can't know entirely by how much, though, until we can test a Phenom system with the TLB erratum workaround applied.

Things just keep getting worse and worse for AMD.

 

[benbaked]

It'll get better with the next core revision. 2008 should be a better year for AMD.

 

[Maverick0984]

Where's that one guy that said the Phenom was so great it was going to destroy Intel, like as a company?

 

[SuperDave1685]

Where's that one guy that said the Phenom was so great it was going to destroy Intel, like as a company?

Hes crawled into a hole and is being beaten by the Yorkfield Gods

I think 2008 will be a much better showing for AMD. Once they can get their CPU's fixed and with a new revision and get their new Radeon cards on track, I think they just may start to be profitable again... for our sake I hope so

 

[AlabamaCajun]

He hasn't been around since after the Phenom launched but we have to give him credit for wanting to go against all the evil that Intel represents. We do hope the AMD can pull off the "Hail Mary Pass" as called in Football (the American Version). The Phenoms are Great at stock and better overclocked on some boards but others just don't have enough tweek to get the results. I'm hitting 2.42 stable enough to do rendering and run all the regular benches but folding@home on quad brings down my rig. I haven't tried any games. Stock is solid 24/7. I need that DFI tweek or RMA the Gigabyte for a DFI and eat the restock. Before someone says get a 6600, every Tom, **** and Harriet has one, I want the Phenom, working DAAMIT!

 

[ps2cho]

Good thing I didn't jump on a new Phenom then

I decided to go for a HD 3870 before getting a Quad Core.

Phew !

 

[SH0DAN]

They are reallt taking a beating on wallstreet now with this news out.

 

[White_Pawn]

so... ~10% slower AND it has slower L3cache than those in the reviews. Ouch.

I hope they can fix and release B3 cpus quickly for their sake.

 

[dipspit]

They've stopped shipment on the Opteron/Barcelona(isn't that what the server quad is called?).

Source: Slashdot

"Errata are not uncommon with new processors, but a problem with the TLB logic in AMD's quad-core Opteron and Phenom processors appears to be quite serious. The erratum is so severe that AMD has issued a 'stop ship' order on all quad-core Opterons. AMD has also blamed this bug for the delay of the 2.4GHz Phenom, despite the fact that the erratum is unrelated to clock speed. A BIOS-based workaround for the issue has been made available to motherboard makers, but it apparently carries a 10-20% performance penalty. What's more disturbing is that AMD knew of the erratum and the potential performance hit associated with fixing it before it launched the Phenom processor. Hardware provided to the press for reviews did not include the fix, conveniently overstating Phenom performance."

 

[hUMANbEATbOX]

They've stopped shipment on the 2.4ghz model.

Source: Slashdot

They never had a 2.4ghz part in the first place. 2.4ghz was delayed, it was supposed to launch with the 2.2 and 2.3ghz parts. They blamed the delay on this errata, implying that problems only manifested above 2.3ghz. That was of course not true.

What these articles are saying is they have stopped shipping ALL quad core parts.

 

[dipspit]

They never had a 2.4ghz part in the first place. 2.4ghz was delayed, it was supposed to launch with the 2.2 and 2.3ghz parts. They blamed the delay on this errata, implying that problems only manifested above 2.3ghz. That was of course not true.

What these articles are saying is they have stopped shipping ALL quad core parts.

Made a typo, I think you were typing your post as I corrected mine.

 

[hUMANbEATbOX]

Made a typo, I think you were typing your post as I corrected mine.

Gotta keep you on your toes.