Thoughts on low-power 1.6-2TB fileserver with PCI-X...?

[ayembee]

hi all. time to stop the lurking now i have a project

i already have 1TB of storage, but it's a mess. mimsatched drive sizes, no backup, and all in my main (currently only) pc's case. although it's very quiet and not too hot, it is no longer expandable, and i'm almost out of storage space. so, time to do something systematic!

the plan thus far: get a Broadcom RAIDCore BC4852, and start with 5x400GB Hitachi 7k400 in RAID5. i already have one of those in the main box, and the card supports online expansion, so i can preserve the data and use it in the array. as i need more space i can add up to a further three 400GB drives.

case: not out quite yet, but have my eye on the Coolermaster CM810

aside from the above, i would very strongly like to minimize power consumption on the rest of the components, eg: CPU/motherboard/PSU. i would also like it to be as near to silent as possible. the only constraint i have is that the motherboard needs to support PCI-X for the Broadcom RAID card... (i believe)

i would very much welcome any thought people have on how this all might tie together! i've seen one Pentium-M board (DFI?) that had a single PCI-X slot... there are also various good quiet power supplies from quietpc.com (i have a slientmaxx 450W in my main box, it's utterly inaudible) but not sure how much power all these drives are going to need!

also, OS -- currently thinking CentOS (the red-hat enterprise linux clone), but again, thoughts very welcome!

[joshwa]

Just curious - but where can you get Pentium M boards from? Do you have a link to the one you are considering? Cheers

[oralpain]

Hard drives list thier power requirement right on the sticker. It should be around 15 watts for each drive, with about 75% of that being +12v.

4-5 good size hard drives is goign to use less power than a high end desktop CPU, or video card would at full load.

If you go with a pentium M, you could easily get by on a quality 350-400w PSU. read some reviews and get one with a very high real world efficency at low to medium loads.

Do you really need the broadcom RAID card? A good modern mobo with 4-8 SATA-II ports should be more than sufficent. An underclocked A64 system would still have plenty of CPU power for a file server, would be far cheaper (less than half the cost for the cpu+mobo and you wouldn't need a raid card at all), and would not use any more power. For example I can run my CPU at 0.8v, 1GHz and it draws about 10-15 watts at full load.

With the money you save tyou could get more drives and set up a RAID 10 or 1+0, wich would be faster than a RAID 5 esp for write speed.

[ayembee]

@oralpain: i think the broadcom is necessary -- data integrity is important to me for this project, RAID 0/1 wouldn't cut it on that front, and i also need the capability to do online capacity expansion. some of the data will be digitial photos, and i shoot RAW images with a pro-grade digital SLR. i may not be professional yet, but losing photos is pretty much my worst nightmare

thanks for the HD power numbers, that helps me get a feel for the PSU requirements. also, i'm curious about an underclocked A64... would like to check out A64 tech too, so might be a good excuse. any links?

@joshwa: here you go
http://techreport.com/reviews/2005q1...f/index.x?pg=1
http://www.gamepc.com/labs/view_cont...d=dfipm&page=1

[oralpain]

I don't really have any links on underclocked A64s, most of what I know comes from first hand experimentation. If you would like me to do some specific tests or have any specific questions, just ask. Generall A64 information can be found nearly every where, including various threads in this forum.

CPUID has a good article on the architecture itself.

All A64s are unlocked going down and most modern A64s have no trouble running at significantly below stock voltages if you drop the speed enough. Current draw is reduced along with voltage and MHz. Below 1.2Ghz I can get by with the stock heatsink and no fan what so ever. With a hardware RAID card and a good network card, even an 800Mhz (the lowest you can set) A64 would be plenty powerful enough for a file server. The only noise would be from the PSU, the disk drives, and maybe a few low speed fans to keep the drives cool.

You can get PCI-E hardware RAID cards and use them on an inexpensive socket 754 (no need for dual channel memory just for a file server) PCI-E board, pair it with an old PCI video card (so you can use the main PCI-E 16x slot for the RAID controler, it's faster than PCI-X), a S754 Sempron (which are just partially castrated A64s), and a single 512MB stick of memory (you coudl even use ECC if you wanted, though it's not necissary for the board/cpu). The whole system, minus drives would cost less than the RAID card. You are probably aware that you are going to be limited by network bandwidth before anything else.

Here is an example of a PCI-E SATA RAID card and a review of the card:

http://www.areca.com.tw/products/html/pciE-sata.htm
http://www.gamepc.com/labs/view_cont...ecapcie&page=1

I'm sure there are others out there but this is the first I've really looked into it.

[SilentDeath]

For cpus, a general rule for power consumtion is:

Mhz is the same, a y% increase in voltage will give 2y increase in total power consumption. so for a 1.4v cpu at 50w, running at 1v will be ~30w. At 2v it will use 92w (still at stock speeds!)

If voltage is the same, any increase in Mhz gives a linear increase in power usage. At 50% of the stock Mhz, it will use 50% power. For a 2ghz cpu at 60w, running at 4ghz would take 120w, asuming it was stable at stock voltage.

So if you take ~50w 3000+ AM64 chip, reduce voltage to 1v, your now at 30w. Reduce speed from 1800mhz down to 800mhz, youve got around 13W of power consumption.

[ayembee]

core network is running off a 1Gbit router, so should be ok there. another role for the fileserver will be to serve files to a media player downstairs (probably zensonic z500, planned released october), so then there will be a jop via 108Mbit wireless, which should still be fine for just serving files to the tv. mostly i need the RAID to be flexible, expandable, and bomb-proof. unless i launch the next google from my home and need web-serving capabilities for millions, heh

the whole thing will be headless, so no need for sound/graphics cards -- will administer it over VNC.

interesting tips about PCI-E, and underclocking numbers, i will definitely follow these up...

[ayembee]

speaking of PCI-E, i see there is a pentium-m motherboard thatr now supports that, but maybe looks a touch overpriced: http://www.gamepc.com/labs/view_cont...d=pm915&page=1

nderclocked A64 is looking better and bettter...

[Matt1eD]

Will you not need a graphics card to set it up at first? (unless you have a spare or onboard)

[Tobeman]

I was just going to post about that AOpen board but you beat me to it. The board would be overkill for a server, it features component, s-video and HDTV output along with D-SUB and DVI. However, it also supports SATA-II and DDR2. But at almost £200, its alot!

[ayembee]

for initial setup i can plug in my existing monitor -- whatever onboard gfx exist will be fine for that, and then subsequently all admin can be done over the network. it's just going to be a quiet dumb block of safely RAID5'd storage for serving the house and downloading large files so i don't have to run the main rig for that (hence the interest in low power -- my main box is rather juice-intensive!)

agree that the new pentium-m board is overpriced for the job!

[oralpain]

This is the least expensive Socket 754 PCI-E motrherbaord I could find form a reasonably reputable company:

http://www.chaintechusa.com/tw/eng/product_spec.asp?MPSNo=13&PISNo=332

I've seen it for as low as 66usd wihc mean it should probbaly not cost more than 50-60 pounds in the UK, if you can find it.

Still need to find out if the baord has the necissary voltage options, many do not go to far below stock voltage. My last chaintech S754 board did, but I can't find much informaion on this one.

[arthurleung]

Just get a cheapo DFI NF4-D, mod it to SLI, stick a 3000+ on it. Stick 2 Areca ARC1220 on it. There you goes, max 16 drives.

Cut the voltage down to 0.96V (or even lower if you don't mind pushing the speed down)
Stock Heatsink will do passive cooling. Then Mod your Northbridge heatsink with a low profile 1U copper heatsink or similar, that will let it cool passively too.

Socket 754 doesn't have PCI-X so don't think about it. Pentium-M's slots are 64bit 66Mhz so you won't get full PCI-X bandwidth as well.

I'm passively (almost, require a blast of air every few minutes) cooling my setup (3000+ stock speed) and its damn quiet even if its naked.

[Mike Fishcake]

I'm going to throw a spanner into the works now and say I wouldn't touch a DFI or chaintech motherboard for a server. For a budget server, I'd use an Asus branded board.

[arthurleung]

I'm going to throw a spanner into the works now and say I wouldn't touch a DFI or chaintech motherboard for a server. For a budget server, I'd use an Asus branded board.

My DFI is stable as hell. Tyan is no good (My S2882 don't fu**ing support dual core because Tyan skimmed on components), Supermicro doesn't support its AMD PCIe motherboard (OEM of a Japanese manufacturer?), how bout an Iwill Dual Opty board? At least the Digital VRM will reduce change of failure.

[oralpain]

I've been able to get bott DFI and Chaintech (as well as abit, asus, aopen, and others) boards running as stable as anything. Set it up right and test it properly, if everything is fine it will probably remain that way.