I'm going to be building a server to colocate very soon, and I've been doing lots of research yet a little experience from my peers at WHT will help tremendously.

I've decided on the following:

Dual CPU (Either Tualatin 1.4's, or Athlon MP 1800's.)

The tualatins are more expensive, but thats the direction im leaning.. I don't want a hsf to fall off and hose my motherboard for the amd server (or some other heat related disaster).

The benefit of the AMD motherboard in my price range is that it has 64bit PCI slots, that would allow me to use the full potential of the U160 scsi host adapter I have (LSI Logic single channel).

Both motherboards have DDR PC2100. I plan on installing 2 x 512 MB ECC Registered memory modules, and upgrade to 2 GB a few months later.

The hard drive will most likely be a 36 GB 15krpm cheetah U160.

I guess my main questions are

1) What are your thoughts of a server with these specifications?

2) What are your preferences with the MP vs Tualatin?

I'll most likely be putting this in a mid-tower case and co-locating it at The Planet to host about 15-20 medium sized sites. I want them to be FAST.

TIA..

Install a Raid system using two mirrored scsi drives plus a Mylex ($400) card. You don't want to be sorry if your single drive crashes.

Go with the Tualatins, espescially in a dual processor machine.

They'll (probably) draw less watts, of course generate less heat, and would do all the hardware in your case a favour by not shortening their life. (By heating everything in the case).

Plus I seem to recall a thread in this very forum about Athlon MP's being a little "unpredictable".

I have had Dual AMD MP 1600's running for a long time before I decided to box it up to colocate it... I think it's pretty stable and I have always been satisfied with AMD

Choose 64 bit pci any day over 32bit.. I have some dual mp's (mpx and k7xpro) and they kick ass in stability.

Some 64bit cards are not very happy running in 32bit mode with a piece of the card dangling off the end of the pci slot, its not pretty ;)

Bite the bullet and put as much ram in the box as possible. 2G or 3G ecc registered. As i've said many times before, the more ram the merrier (and faster) The box will be. You can have all that system, but if your box starts swapping, you will be in slow land ;)

Ram prices aren't that bad right yet. Get 2 1G ECC registered sticks, and do it right..

most low end server motherboards, max out at 3.5gb due to pci mapping and the 4gb limitation of the 32bit cpu. So the returns diminish between 2-3gb and 3-4gb. I'd stick with 3GB max.

I have a dual intel tulatin 1.13ghz 512ks on a tyan mobo.
Great so far........I got 2 cpu fans (off course), and 3 more fans in the case. 2 back and one front.

The server has been amazing so far. It is running very very cool too compared to the other co-locate server around.

I however did not go the scsi way. I went with 4 ide drives running onboard raid 0+1. Rebuilding the raid on one drive took approximately 20 mins. IDE raid is a cheap solution I took, and I do regret it =p but then again technology moves so damn fast, why spend kazillion dollars to get the job done when a crappy machine can do it too.

does ide raid not rebuild in the background? the adaptec's do. Just pop a drive in, and it will automagically rebuild in the background..

Until I can afford to go raid I'll just be backing up to a spare ide drive in the machine, with off-site backups done weekly or something.  

Is the IDE raid your system bottleneck?  Right now I have a single cpu server with a single ide disk, and a some-what popular forum is killing it.  I will be moving up from a 1.7ghz P4 with a 40GB ide disk, 512MB sdram.

ram + disk i/o are always bottlenecks. If you have a system load but idle % processor, then its 99% likely your cpu is spinning its wheels waiting for (disk,etc) to happen.

The idle %0 should be low and most of the (90%) user space cpu time in top for a healthy system. high system % times can be indicative of inefficient or backlogged i/o as well.

I'll be running most likely two scsi disks, I was thinking of running 1 disk with everything on it, and one for just mysql databases.. I would assume this would speed things up a bit, what are your thoughts?