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"The random read performance depends on four factors, not one: the areal density, the seek/settle time, the rotational latency, and whether the data is in the drive's buffer cache already."

About 99% of random read performance depends on RPM, the other 1% is everything else. As for areal density and buffer: Techwarelabs short stroked a 7200rpm 1.5tb to 300gb and only got 10.3ms while 2004's (ok 7 yrs not 10 like I originally said) Fujitsu MAU3147 15,000rpm SCSI drive has a average random access time of 5.7 milliseconds. That Fujitsu is a 73gb drive with a much smaller buffer (8 vs 32mb) and much lower areal density than the 1.5tb drive and it's still nearly twice as fast at accessing data randomly. In case you think that's some kind of fluke Tomshardware tested a 450gb 15,000rpm SAS drive. It got 6.0ms.

I've tested 15,000rpm drives on xp, vista and 7. Boot-up and starting programs is night and day difference, but you don't really notice the difference any other time.

"it's fairly sequential reading (of multiple mostly sequential stripes in alternation), which is why the modern 5400 RPM drives spank older 7200 RPM and 10k RPM drives."

True, but very few people do a lot of sequential reading, unless you're doing a lot of video editing with large-ish files, ~100+ mB, where a older 50mB/sec 7200rpm drive would be beat by a modern 5400rpm 100+ mB/sec drive due to the areal density, but you have to go back several years to find a 7200rpm drive that only does 50mB/sec.

"I'm sure a modern 3TB drive would match or beat a 10 year old 15k RPM drive if you used short stroking* [tomshardware.com] on the modern drive."

You would be wrong. 2004's (ok 7 yrs) Fujitsu MAU3147 15,000rpm SCSI drive has a average random access time of 5.7 milliseconds. Tomhardware short-stroked a 7200rpm 250gb SATA drive down to only 12gb and only got 8.5 milliseconds. They also tested a 15,000 SAS in the same test and got 6.0ms.

Techwarelabs short stroked a 7200rpm 1.5tb to 300gb and only got 10.3ms

There is no replacement for RPM.

There are some other good looks at RS780 performance:

http://www.pcper.com/article.php?aid=527 - looks at Hybrid CrossFire with several games in real world testing as well as GPU overclocking; also features the new AMD X2 4850e processor
http://www.techwarelabs.com/reviews/processors/780g-and-4850e/ - looks at both the chipset and CPU
http://techreport.com/articles.x/14261 - good motherboard review
http://www.bit-tech.net/hardware/2008/03/04/amd_780g_integrated_graphics_chipset/1 - tests HQV and HD audio systems

Looks like TechwareLabs had the first review to go live: http://www.techwarelabs.com/reviews/processors/barcelona

I remember an article published on Slashdot a year or two (or three or four?) ago about a memory timing analysis. A copy is available here:

http://www.techwarelabs.com/reviews/memory/memory_ timings/index_3.shtml

The net impact of the CAS latency: 0-0.002%. Almost _nothing_.

The great thing about this article is that it goes into just about every aspect available in the bios, giving you a good idea of what _does_ work (a brief scan-through reveals clock speed as the primary contributor, dram command rate and Active to Command (Trcd?)).

Happy reading.

-DrkShadow

http://www.techwarelabs.com/reviews/video/ati_rade on9700p/

http://firingsquad.com/hardware/r300/default.asp

http://www.anandtech.com/cpuchipsets/showdoc.html? i=1685

Maybe 4 years is pushing it, but just 3 years ago you could have had a 9700 Pro and 2 ghz Athlon XP processor. That same setup would still run most games just fine today.

Thanks for the suggestions. The RDC is a good idea, but as you mention, I'm not positive that it can handle the framerate of video. You could also use the laptop as a RDC server and transmit the audio to the client/desktop - not sure if that works well, either. Still, it seems like the only viable solution that isn't platform specific.

The outplug stacker is interesting, although I don't see how it helps solving the issue - you need another plugin that facilitates transmitting the audio over ethernet and reproducing it on a target computer. The stacker simply enables you to send it somewhere and listen to it locally at the same time. Still, I never knew such ethernet tunneling plugins existed for Winamp - that said, I don't own any standalone device, but a desktop computer should be able to look like one to Winamp. The output stacker plugins were in fact removed from Winamps DB, under a ban of Streamrippers, see discussion here and here. Somebody was nice enough to post it to some web board (shame that /. doesn't allow file uploads ;).

The USB sound card doesn't really help in my situation - the laptop has got a perfectly fine (stereo only) audio out, and the internal sound chip is good enough for casual listening. But I don't want to connect it to my speakers every time I come home - the constant re-connecting, especially considering that my desktop is connected to them with something like 4 cables for surround audio would be extremely painful. And with wireless ethernet, the only cable that I grudgingly am willing to accept at home is a power cable.

I'm really kind of surprised there isn't an elegant solution already - I always figure it's a problem many people would like solved. But then again maybe that's what you always think about your own problems. :)

See this. It appears that DDR performance is not affected by CAS. I do remember the PC133 days, though, and CAS did make a difference back then.

Also, running RAM at lower than its rated speed doesn't necessarily ensure stable operation at a lower CAS latency.

http://www.hothardware.com/viewarticle.cfm?article id=592&cid=1
http://techreport.com/reviews/2004q4/athlon64-fx55 /index.x?pg=1
http://www.bit-tech.net/review/364/
http://www.short-media.com/review.php?r=266
http://www.pcstats.com/articleview.cfm?articleID=1 666
http://www.tbreak.com/reviews/article.php?id=331
http://www.amdreview.com/reviews.php?rev=fx-55-400 0
http://www.techwarelabs.com/reviews/processors/amd 4000_fx55/
http://www.hardocp.com/article.html?art=Njc1
http://www.xbitlabs.com/articles/cpu/display/athlo n64-fx55.html
http://www.sudhian.com/showdocs.cfm?aid=614

Spending time is nice but This is the page I think they should have linked to .
Basically in the review they compare different chips (2.4Ghz, 2.8Ghz) etc. against each other all with 800Mhz FSB

This case would look at home in any AV setup.

Cooler Master 610-GX1

A bit pricey though

A few more pictures.

If you submit a /. story to a site that you run, please check your bandwidth first to see if it can survive the Slashdot effect, or at least put up a less-graphic version of the page.