VIA CPU - anyone using with Giga?

[Doug Marshall]

In searching for a silent computer solution a friend has recommended trying the low-power VIA CPU. It\'s only 900 mHz but it requires no fans and draws only 5.6 watts. Does anyone have Giga experience with it? Comments? - Doug

[Doug Marshall]

OK, I\'ve taken a tentative plunge with one of these. I\'ll have a unit to test in a few days and will report any Giga success/failure. I\'m told I should not be able to hear the PC with it sitting next to me on the desk. I like that thought.

[composer22]

Well my question ha sgotta be...is this just a CPu or a mobo too? And what about HD, peripheral and memory cooling? You\'ll still need a fan?

I thought about buting a small isolation booth and sticking my puters in that

[Alan]

I haven\'t heard any good reports on this CPU so far,just the opposite.Supposedly it has next to no FPU and is intended for buisness and non fpu consuming tasks.Maybe they upgraded it though.

[Doug Marshall]

I\'m getting the test machine Friday. It\'s being assembled with the hope that it will be successful as a small, silent Giga box. The silent part they believe they\'ve worked out. What remains to be seen is whether Giga will run well on it. I\'ll let y\'all know what we find out. - Doug

[composer22]

Doug is one tightrope walking kinda guy here, and I hope it not only works out, but that we can perhaps follow in his foot step

[killerbobjr]

Brave man indeed. My guess is that for most Gigasamples it will work quite well. You\'ll probably get high polyphony counts, assuming you have a good hard drive to start with. I was able to get 150 pop and click free voices on my AMD K6-500 with 5400 RPM SCSI drives. The only trouble you\'ll run into is if you either try to use NFX effects or load a Gigasample that uses lots of filtering or transposed samples. The FPU on the Cyrix/VIA chips run at half the speed of the main CPU and it\'s not pipelined.

For more info on building a silent PC, check out VIA\'s page at: http://www.via.com.tw/en/viac3/C3_silent.jsp (\"http://www.via.com.tw/en/viac3/C3_silent.jsp\")

[Alan]

It might work if you don\'t use any effects.If you do click on the NFX,dive for cover!!! images/icons/grin.gif images/icons/grin.gif images/icons/grin.gif

[Doug Marshall]

Hi All, OK, testing of the VIA CPU is done. Verdict first: no go. This was a 900 mHz Win 98SE machine, 512 RAM, 1 Barracuda IV drive, (I know it should have had two, but we had a big vcache and observed that the disk activity was essentially zero using our samples), Echo MIA card, not sure on the MOBO, think it was ASUS.

Performance began to stumble above 60 notes (concurrently running a sequencer, which I have to in my application). All of my samples have release triggers and I\'m guessing that these caused some difficulty because the note lengths were extended and releases became sloppy (we\'re talking hanging on for extra beats here). We tried a couple of different MIDI interfaces (including the integrated VIA port) and performance was equally bad with all. And it was prone to crashing when the load went up.

If there was a plus side, the small case was wonderful (as long as you don\'t need to add any peripherals) and the virtual absence of physical noise was most welcome. I would recommend a box like this for a TV room

So the search for the silent, low power/low heat, Giga box will continue. I\'ll keep you posted! - Doug

[killerbobjr]

Hmmmm. Interesting results on your Cyrix CPU. Just for kicks, I popped in an old Celeron 366 in one of my test machines (VIA chipset, Seagate Barracuda IV, M-Audio Audiophile). This machine normally can reach 160 voices with an 800MHz Pentium III Coppermine core CPU without breaking a sweat. The Mendocino core Celeron CPUs are roughly equivalent in power to the new VIA/Cyrix chips for matching frequencies. I was able to get about 40 voices at 366MHz. I remember getting at least 90-100 voices in my old BX based machine when I overclocked the Celeron to 550MHz (100MHz bus) using SCSI drives. I would have expected the 900MHz VIA/Cyrix to get at least that. I\'ll have to buy one and try it out on the various motherboards I have here in the bunker.

For silent system alternatives, you can get a Pentium III Tualatin 1.4GHz and underclock it (100MHz bus will get you 1.05GHz, 66MHz bus will get 700MHz, both fast enough for 160 voices). With a 100MHz bus, you will dissipate around 25 watts and can use a low noise heatsink:
http://www.overclockers.com/articles577 (\"http://www.overclockers.com/articles577\")

At a 66MHz bus you\'ll be dissipating around 15 watts, which means you can run a passive radiator:
http://www.zalman.co.kr/english/product/cnps6000Cu.htm (\"http://www.zalman.co.kr/english/product/cnps6000Cu.htm\")

For a really radical approach, you can go with a water-cooled system. My main machine is a water-cooled AMD Athlon 1.2GHz with a low speed 5\" fan (runs at 7 volts). I get less < 30dB noise levels.

[Doug Marshall]

Killerbobjr, I think a large part of the problem can be pinpointed to the release triggers. The sustained polyphony was OK at 60 notes but I couldn\'t really go higher because of the triggers doubling the polyphony when you release the keys. This is where the sloppiness came in and if you really pushed things the machine would crash totally.

Thanks for the suggestion on underclocking. I\'ll look into it. - Doug