Articles like this make me wish we could rate articles. Great article!

how bout amd???

Next step is to find a workaround.
I don't yet have a system to experiment with but have a few suggestions.

How about setting process affinity and raising priority of the processes involved with disk access?
On my Dell laptop, I use an application called SpeedSwitchXP that makes it possible to manipulate the C-state policies for Demote/Promote-limits on microsecond level. It seems reasonable that introducing a little more hysteresis in the C-state policies would keep the CPU faster between disk operations.

Run 4 & 5 for X8SAX show the same stuff disabled (and a capitalization missed) .... mistake?

Btw, does this assessment count for raid usage as well? I'm seeing fairly irregular speeds on my raid 5 (5x500gb) on my ich9r based system. Gigabyte said it was because I was using the raid as a system drive. So I created a raid 0 of 2x500gb drives for windows, but the irregular speeds on the raid 5 remained.

Just out of curiosity, will the performance be affected if a dedicated raid card is used to connect the SSD?

@cedriclam: Hard to say, but I'd guess yes. We will look into this again soon, using different platforms.

We didn't have two X25-Es to check if this is also the case for RAID setups, but my feeling says yes. The same applies to other controllers, but we'll look into this in greater detail soon!

This may be a case of benchmarks not showing what true real world results would be. Since most things that would truly stress the hard drive performance would most likely also be using more CPU so they would not be in the low power states.

Just thinking out loud.

Tomshardware dudes:

Today I feel a deep rant, giving you 5 stars for this investigation.

Keep doing good work.

Nice work on the article! I've got a couple of questions though:

Does this affect I/O performance as well, or is it just throughput?

and,

Do you get the same affect on AMD systems?

patrick, what car are you driving in your avitar? (just curious)

Does the SSDs support Write Caching (in disk properties), and if so, have you turned it off? It's been my experience with regular HDDs that turning off write caching has an impact on CPU usage...

For god sake!!! I own an Opteron, but please you AMD spammers are killing us! Who the hell would buy a crappy slow $200 Phenom to pair it up with a $800 SSD?

Buy a Tata $2500 car and put some 26in wheels on it too!

As far as my knowledge goes, Phenoms II are not slow. ;-) Sure they are slower than core i7, but they are fairly cheap. Not only core i7 can benefit from SSD.
I'm sure Tom's will test this issue on an AMD platform too. :-)

Do MLC flash drives also exhibit the same slowdown with the power saving features turned on?
I know they are much slower to start with, but do they also get affected equally?

Somebody who need the fastest SSD, on a limited budget, and found that AMD does not have the energy-saving performance issue (Who knows?. for THAT reason we want to see the AMD benchmarks)

please benchmark some of the new OCZ SSD's now that you have a new reference system, i've been dying to see real world numbers for the OCZ apex and especially the VERTEX series! Two drives that claim decent performance without completely emptying my wallet.

In the top paragraph of the "Outlook, Conclusion And Remaining Questions & Answers" section the second sentence reads: "...and the X25-E (for consumers)" That should probably be X25-M

Otherwise, very interesting article.

-mcg

If you are worried about performance are you going to be running with the power savings stuff anyways?

To me, the bigger issue is the amount of dependency this setup has on the CPU. It would be interesting to see this same set of tests run through a hardware based SAS or SATA RAID controller on a single drive (no RAID, just a drive).