questions about building a rack mount box

jjleprikon · Post by **jjleprikon** » Thu Nov 30, 2006 1:14 am

I am building a ZM box with a 1.4G athalon processor, 6GB drive for the OS, 300GB drive for data, I am shopping for more memory now, looking for 512M to 1GB - will the 1GB really help, or is 512M good? I have a 2u server case, an ebay capture card, and a BW camera. The system is working with the one camera. I will be adding a second camera in the next few days. Right now I have everything setting on my tabletop and running. I am ready to put it all into the case. I have never built a system other than a regular desktop. I have a pci riser card that came with the case. It has 2 slots on it and it plugs into one pci slot on the board. How can 2 pci cards run from 1 slot on the board? Do I need a special motherboard for this kind of riser? I have seen risers that have wires that plug into separate pci slots on the motherboard, maybe thats the kind I need. Anybody know?

pathway · Post by **pathway** » Thu Nov 30, 2006 4:37 pm

I have only run ZM off the live CD... and from what I can tell, ZM is not extremely memory intensive at it's base... Of course, I expect memory requirements to go up as the variables increase (Number of cameras, size os images captured, framerate, etc). Also, how Linux uses extra memory for caching means that the extra memory won't go to waste. Last, you can save memory by not running X on your server. I think if you went without X, 512 would be enough.

About the PCI riser: Your motherboard should handle it just fine. PCI is a bus, so you won't have a problem with the multiple cards.

I've built 1u, 2u, 3u and 4u systems before. I love how many servers I can have in a single space... and with today's powerful machines and free Virtual software (Xen or VMware) these machines can be used more efficiently.

But building a 2u from scratch... I must say that your mileage may vary with this... as I've seen motherboards that won't fit in the case, and I've seen powersupply cords that are not able to reach the motherboard... When you leave the world of Full Tower cases (and even sometimes in the world of Full Tower cases) sometimes things just don't fit right.

I've found the most success in purchasing rackmountable server barebone systems... I recommend Supermicro, Intel or Tyan. These are Cases, Motherboards and Powersupplies all bundled together and designed to fit together. They start at about $500, and go way up from there. (I shop at Newegg, check out Networking -> Servers -> Barebones Servers.) But since you're already invested with a system...

Some "Gotchas" you should look for: Be careful you don't ground your motherboard somewhere. Odd motherboard mounts sometimes appear in these cases. Make sure you have a 2u CPU fan... If you don't, and your fan "barely fits"... you might limit the airflow. (Some cases have passive coolers but a near by case fan. This works well too.) Last, be prepared to do some Dremeling to your case if need be. Especially cheaper cases... sometimes things just are in the wrong places.

And with that, I must wish you good luck.

--Pathway

jjleprikon · Post by **jjleprikon** » Thu Nov 30, 2006 6:16 pm

Hey, Thanks for the excellent post! The used case I got cost me < $30 and it has a power supply, 2 fans, floppy, CD drive, the riser, and an assortment of power and data cables. It has metal standoffs, so when I attach the motherboard I will use some nylon washers and bolts (if I can find the right size), thanks for that tip. The motherboard holes seem to match the standoffs. I guess I'll see for sure, Hopefully this weekend.

The processor fan is very close of the case, and I think air flow will be an issue, I thought I would just drill holes to allow air to flow, I thought either one big hole or a series of smaller ones to make a mesh opening, I will check into the 2u fans though, that sounds much easier!

Ive got my Dremel ready to go should the need arise, Thanks again for the excellent response!