We have a small business and I ordered 4 new Dell 4550's (3.06 ghz) a few weeks
apart. They are all identical except for one thing, the case fans. The model #'s on all
4 are JMC/Datech DS9238-12HBTL. Now the difference is on the first 2 that came,
they are DC12V 1.50A and the second 2 are DC12V 1.70A. They also do have different Dell part (not model) numbers so they are definitely not the exact same.

Now my first question is, does going from 1.5A to 1.7A make that much difference in the
sound/noise? The 2 computers with the 1.5A are totally silent (yes silent not quiet). I have had many Dells in the past and am completely amazed as how silent they are. So much that if we put our ear right up to them we can barely even tell they are on and they are silent when standing. In a quiet environment, when I walk up to them I have to look on the front led to make sure they are on. The
second two computers make a huge sound difference. You can tell they are on from
even 20 feet away. They are not annoying like older Dell's and are very livable but
nothing compared to the silent two. BTW, I did unplug both computer's case fans and found that was the noise source. The fans are not bad or clicking/humming or anything, they are just louder...

I called JMC and got the general specs for the fans. She said 1100-5100 RPM +/- 10%, CFM 100 and 51 DB. She didn't know if that was for the 1.50 or 1.70A. I was very surprised to hear that the DB and CFM rating was so high and the fans so quiet (although SPC did give the JMC 9232-12HB TL an "interesting" recommendation).

So my other questions are, does the fan normally run at 1100 RPM and only go up 5100 RPM when needed? Is there any (many) RPM range(s) in between? Does the CFM work the same way, is 100 CFM when it kicks up to 5100 RPM and is it say at 50 CFM when it's only 1100 RPM?

My last question is can I get away with putting Panaflo's on the other louder 2. I was thinking the FBA09A12L1A, 2100 RPM and 42.7 CFM. One case fan on each system of course. I just wanted to make sure that the lower CFM would be ok? I do not game or do any intensive tasking.


By the way on another note, in case anyone is interested, the hard drives have something along the lines of this kind of grommet mount:

http://www.earsc.com/cmsframe.asp?SID=6 ... /main.php3

and the case fan has the elastomeric fan mounts like these black ones:

http://www.earsc.com/cmsframe.asp?SID=6 ... /main.php3

That is the only fan in the system other than the PS fan. The CPU/heat sink has that
hood over it (no fan attached on top), and the case fan sucks the warm air out. I think
the plastic outside shell of the case helps reduce vibration too. I am very impressed to see that Dell is trying hard on sound solutions. It seems strange that they do not advertise any of that stuff at all.

Oh also important to know is, the power supply now is an ATX standard one. As I said, I am just noting all this for interest. I know that the real way to go is buy your own
components and do it yourself. The Dell systems were cheaper for me and before I
started reading this group I didn't know any better either. But I am pretty happy with the silent Dell's, I don't know if I could have done better myself.

Thanks!:)
Chris

Yea its only cheap to buy dells when the 3 deals that they offer at a time line up good with the system you want to buy. I bought the dell my mom has and its a 2.4ghz, 512ddr333, 80gbHD, gfmx, with 48x burner, 19" trinitron monitor, and it was only $900 w/shipping 6-7 months ago. I also noticed that there is always a program called system idle process running. I dont know if this is standard for windows XP or if its a cooling program like cpu idle? Anyone know if this is just a standard XP thing or a cooling program?

It's an NT thing. Standard in Win NT, Win2000 and WinXP. It's a process that runs to occupy the processor when it's not executing other threads. This is the time that the "Halt" command is being given to the CPU (that's what "CPUidle" does, as third-party software on Win9x systems). This idles it and makes it run cooler. I've discussed this in more detail in several other threads. This process should generally account for 95+% of your "uptime" unless you're doing something CPU-intensive like running some Distrubuted Client software.

The box I'm typing this on shows 97% for system idle time. It's my general use box and has been online for 209 hours since last reboot. That 97% is probably pretty typical usage for most peoples' systems. On the other hand, I'm stress-testing an OC on my other system right now by running Prime95 and the "System Idle Process" shows 0% whereas the "Prime95" process shows 99% for 34 hours.

Ok I thought that is what it was, I just wasnt sure. I use to know all the programs on 98 but XP is new to me and I dont know what half the programs that are currently running actaully do. I think 98 had 3-4 programs that had to run systray, explorer, and another one??? but XP has like 10+ at least on this computer.

XP does not actually come with a lot of system tray icons, it's the third party that usually brings the most. Graphics, sound, lan, modem drivers etc.. and any software you install can add system tray icons. I am pretty sure Windows XP don't have a icon to make your CPU run cooler while the CPU is idle. I have XP Pro and I only got about 3 sys' tray icons. I avoid hogging up the resources. Most of those icons are normally useless so I disable them when need be and appropriate to do so.

I dont mean system tray, I mean going into control alt delete and seeing everything that is currently running. This comp has about 4-5 sys icons but 28 programs running, and alot of them are XP files.

Here's a pretty thorough XP Services (that's what a lot of those running apps in Task Manager are - services) Guide. Browse around this guys' site and you'll find a lot of answers. You'll also find a goodly amount of BS. I'd be especially careful about turning off services just because he says it's safe. WinXP has very good memory management and even if a service is running it doesn't use much, if any RAM unless it is needed. Therefore you don't save much, if anything by turning off various services. It's not at all like Win 9x where you could go into msconfig, stop a bunch of superfluous programs, reboot and end up increasing your system resources. WinXP uses resources much smarter than that and you may very well end up turning off something the OS needs to work correctly. A lot of services are dependent on other services to work, as are a lot of apps. Sometimes this relationship isn't very clear so it's easy to mess something up if you don't know exactly what you're doing.

As a hardcore 9x tweaker (98lite to start, and tons of reghacks, etc) when I first started using Win2000 (services + memory management almost identical to WinXP) my first thought was to start tweaking the h*ll out of the OS to improve performance. After a while (and more than a few bad experiences.........thank goodness for Drive Image) I started realizing that the OS did a pretty darn good job of resource management all by itself and now I basically leave things alone. There are a few services that I disable (Remote Registry, Automatic Update, Error Reporting and a few others) but otherwise I pretty much leave things alone.

ehhh...maybe this is more than you wanted to know but I just finished a cup of coffee so my fingers need something to do.....

No any info is good info, well except for BS but I expect that from people in forums

Thanks, this was a very informative thread and I learned a few new things. Unfortunately it went way off track of what I asked above;) So I will give it another shot in a shorter question format in a new thread.