Expert: Bobbert - 11/1/2007

Question
QUESTION: I would like some advice on selecting a desktop PC.  

I need at least 2GB of RAM but would prefer 4GB or 8GB.

Also, I will be running applications that require a lot of processing time and would want at least 3MHz or more.

The machine will be used to run data intensive business simulations but also be used for business applications (e.g. Microsoft Office, QuickBooks, etc.)

I also need the machine to be very reliable.

I’d appreciate any suggestions.


ANSWER: Ok, well, firstly 2GB of RAM is the max you should consider purchasing, and here's why:

4GB of RAM won't be recognized by any 32-bit operating system (Windows 2000/XP, most versions of Linux and BSD, Vista 32-bit, etc) so its wasted resources, and while Vista 64-bit and XP x64 can recognize 4GB of RAM, no application on the market can make any sort of use of 4GB of RAM (because any application that has that much resource demand already has provisions made to handle it, so it doesn't eat up physical memory).

8GB of RAM is positively absurd for a single user system, and isn't commonly seen outside of commerical application servers costing in excess of $10,000, notice that these are machines designed to serve hundreds or even thousands of users concurrently.

I'm not sure what you mean by the "at least 3Mhz or more" comment, however the clock speed of the CPU doesn't matter much relative to its performance, not to mention that modern CPUs have clock speeds exceeding 3000MHZ in some cases, for your type of workload (from what you've described so far) a basic dual core CPU is more than enough processing power, something like the Athlon64 x2 3600+ from AMD or Core 2 Duo E4500 or E6550 from Intel.

I'd suggest looking at Dell's Small Business offerings, such as the Vostro 200 line:
http://www.dell.com/content/products/productdetails.aspx/vostrodt_200mt?c=us&cs=
A new system should be possible for around $750 with monitor and shipping included.

-bob


---------- FOLLOW-UP ----------

QUESTION: Bob,

Why do most desktops have slots for 4MB of RAM, if 2MB is the most that could be effectively used.

I've also read about some machines, I think HP, that come with 3MB of RAM.  Is that just a sales gimmick since from what you said, all things being equal, 2 MB is the most that should be installed?

Thanks,

Steven

Answer
Well, most current desktop systems can support up to 4GB of RAM, mostly due to 4GB being the theoretical limit of a 32-bit operating system, however there are various factors which reduce the memory available to the kernel when 4GB is installed (the OS will start allocating the RAM above ~3.2GB to various buffers, like PCI Express, which is what happens to the extra RAM).

3GB of RAM is the most you could practically expect to use, however it isn't normally considered because 3 isn't a multiple of 2 (most things in computers are derived from multiples of 2, so 3072MB doesn't normally come to mind as a viable option). 3GB of RAM wouldn't give much of a performance expansion over 2GB, although given how low DRAM prices are currently, I don't see any negatives going for 3GB, given that its going to be recognized by the system entirely, regardless of what OS you choose (ok, take that within reason, amazingly old or proprietary OS' are obviously going to have issues), yet doesn't break the bank (not that 4GB does, generally speaking, but some resellers drastically increase the price of memory when 4+GB is purchased).

Honestly I wouldn't suggest HP, due to seemingly innumerable experiences in the field with HP systems being generally less reliable and less durable than their Dell competitors, I'm not saying HP isn't a good product, Dell just generally offers a more solid product (At least from an IT perspective), which is why I would suggest Dell over HP, not to mention that Dell's business-class support is second to none.

-bob