recommendation?

[cscgal]

As I mentioned in a previous post, I'm running off of a PIII 450 Mhz with 128 mb of RAM and busting at the seams.

I'm looking at upgrading to one of the following 3 solutions:

Pentium 4 1.8 ghz with 512 mb of SDRAM
Celeron 1.8 ghz with 1024 mb of SDRAM
Celeron 2.0 ghz with 256 mb DDR RAM

Which of the above would be the best solution for a single vBulletin powered site? Nothing other than Apache w/ vBulletin will be running on the server.

As far as I know, ram and ram speed are most important over processor speed. Please don't suggest a machine with specs higher than any of these three, because it is most likely above my price range. In addition, I am looking for a long-term solution that I can grow into (if possible).

My main concerns are ...
Is a Pentium 4 that much better than a Celeron?
Can I sacrifice cpu power for more RAM?
Can I sarcifice more RAM for faster ddr RAM?

My site currently has 50-150 concurrent users, while only 5-10 are logged in users w/ posting permissions.


TIA
Dani

P.S. Please get back to me asap because I'm planning on making this purchase in the morning and just want some last minute feedback!!

[Odysseus]

a) Pentium 4 1.8 ghz with 512 mb of SDRAM
b) Celeron 1.8 ghz with 1024 mb of SDRAM
c) Celeron 2.0 ghz with 256 mb DDR RAM

Which of the above would be the best solution for a single vBulletin powered site? Nothing other than Apache w/ vBulletin will be running on the server.
Best for vB is server B, second is server A, last is server C.
You should NOT put even one cent into a 256 MB machine, even if it's DDR-Ram!!

My main concerns are ...
Is a Pentium 4 that much better than a Celeron?
Can I sacrifice cpu power for more RAM?
Can I sarcifice more RAM for faster ddr RAM?
Yes, yes and no. :)
You can sacrifice anything in order to get more RAM. SD-Ram still is good enough compared to DDR-Ram. Quantity before quality!

Of course, the P4 would be the best choice for your CPU. A Celeron 1.8 is significantly slower than a P4 1.8, but if you can double your RAM to 1024 MB it is worth it! Your MySQL 4.0.x query cache will be thankful to you. :)
Maybe you can afford a Celeron 2.0 and 1024 MB DDR-Ram ... would be quite a good compromise.

I would also recommend a quick harddisk like WD Raptor 36 GB or some good SCSI drive, as database performance also depends heavily on your HDD - not only RAM! You should also think about a 2nd drive for backup reasons or to store your database dedicated on one harddisk. (Again, the latter will significantly enhence performance).

My suggestion:
- Celeron 2.0
- Intel mainboard
- 1024 MB SD-Ram (2 modules will be cheaper than one 1 GB module, I think)
- good 7,200 rpm IDE HDD for system, webserver, logfiles and DB-Dump-Backup (maybe a "Seagate Barracude 4 7200.2", 60 Gigabyte)
- "Western Digital Raptor", 36 Gigabyte, 10,000 rpm as dedicated MySQL data storage drive

Low-End hardware at it's best! :D
Should be able to handle at least 300 users online.

[cscgal]

Thank you so much for that feedback. So you're saying I should still prefer a Celeron 1.8 ghz machine with 1024 mb RAM over a Pentium 4 1.8ghz with 512 mb RAM ??

I don't think I will be able to afford SCSI, unfortunately :( However, I will consider using two hard drives and dedicating one of them to MySQL.