Easy question

Impossible to say from what little you've said.  An Excel spreadsheet's calculation performance is highly variable depending on how (well) it's been designed and implemented.

My advice is to run some benchmark tests.  In my experience, Excel performance is MORE dependent on DISK I/O PERFORMANCE and MEMORY throughput than on CPU speed.  But again, your mileage may vary depending on the limiting factor in the spreadsheet.

Again, RUN SOME TESTS so you can be an informed buyer.

Mr. Options,

Here are your options:

http://www.buympc.com/smallbiz/store/desktops/overview_clientpro.html

http://www.dell.com/us/en/bsd/products/line_desktops.htm

http://www.gateway.com/work/products/sb_eseries_catalog.shtml (choose the E-400 and up series)

These are the top three PC Direct Vendors. Most, if not, all of the PCs you will find at the above links have fast processors and DDR memory. =)

Dude, get a Dell.  Spend $1,000 on it and you will be able to do plenty.  But hey, Dell has already been mentioned.

I personally think Dell is a bad choice... they are over-priced for what they have to offer in a system.

You ought to custom build your own Server.

You'll need a average processor ----> 2.0 mhz (Intel or Amd, but preferably Amd)

lots of memory ----> at least 512 to 1 gig of DDR ram

and don't forget you'll want a couple of SCSI hard drives.
Go with Western Digital. DO NOT USE IDE, I REPEAT DO NOT USE IDE!

There you go.

Best of luck to you!

Can the average user build one for less than they can buy one?  Not even.  There is also an issue of problem parts and pieces.  At least the Dell systems have gone through burn-in testing.  If they fail they are not sent out.
Everyone is entitled to their own opinion, but I wouldn't build a system that required a constant uptime because of cost and reliability issues.

I personally think Dell is a great choice.  You get a lot for the money, their service and support are excellent, especially when compared with others like Compaq/HP and Gateway.

You cannot even buy the components to build a system for when they sell a warrantied, built, configured system for including the operating system.  In fact, you can spend more than the cost of a complete Dell system at your local computer shop buying only a CPU, motherboard, and a copy of Windows.

On the Dell vs. Compaq, etc. issue, if you are mostly a hardware novice, Dell is a good choice. They are the largest PC manufacturer, and have a good support web site. I hear bad things about Gateway customer service, but also talk to people who spent 1 to 2 hours on hold before they got through to Dell technicians.

If you are comfortable picking your own components and such, buy a generic PC from the Internet. We can help you choose quality components, and you will get a 20% to 30% lower cost. The quality will be comparable, but the cost considerably lower. Dell can be competitive, but when you do things like up the base RAM, they will be much higher-priced than the Internet sources selling the same thing.

As for the comments about SCSI, these seem more religious than technical. In a network file server, SCSI is superior, but not really on a personal PC so long as you choose one of the high performance drives. IDE costs considerably less, and any performance difference would be so small you would need to run benchmark tests to find it. If you want maximum performance, you could look into IDE RAID, but again the performance difference is quite small. Look instead at specs like drive RPM, cache size, access and throughput speeds.

As for how much you need to spend, excluding the monitor, you could spend $500 to $1500, but go with the recommendation for lots of RAM, preferably enough that all or most of your spreadsheet resides in RAM so you are minimizing disk access, which is a bunch slower than RAM. Buy a 19" or larger high end monitor so you can see lots of data without doing a lot of scrolling. You can get a generic high performance good quality PC with all the features you need, with a good monitor, for about $1000. You would be buying a lot of the same components a company like Dell would sell you, but not paying their markup and considerable overhead.

It would also help if you would load Windows Explorer and tell us how large this spreadsheet is (in bytes/MB), and the size of the Access database, too.

Oh, and you asked for the cheapest. Please change your mind about that. Don't buy the cheapest, buy the best value. How much is your time worth? Buy a system that will meet your needs for at least the next two years. Generic is better value than major brands. AMD processors are better value than Intel. Buy Maxtor or WD IDE drives, but buy 7200 or 10,000 rpm with large cache and high performance, not 5400 rpm low end. Buy lots of DDR RAM. 128MB of RAM would run your spreadsheet, but slowly. 1GB or RAM would probably run it quickly.

Yep.  EMachines is quite cheap.  It is also a perfect example of "you get what you pay for."

Hi OptionsMM,
The most relevant comment is the first, suggesting you test the software in question on any existing computer.  Using that as a guide, something can be recommended.  The recommendations for specific specifications are just wild guesses in the dark that you should ignore.  (I am especially entertained by the advice from "scsi" to avoid IDE at all costs, a meaningless blanket statement)  You've effectively asked, "what kind of vehicle should I get to carry around a lot of stuff?" and the potential answers range from "a pickup truck" to "a container ship."

Run the setup on any computer you can find and let us know the results.  ONLY THEN can anyone here do more than throw out wild guesses.

Did you write this spreadsheet yourself?  I don't know the operation order for Excel, but I do for MiniCalc (a PalmOS spreadsheet).  So as an example, MiniCalc goes across each row first.  So if 1B depends on 2A, this requires two passes of the sheet.  In this example, the sheet should be rearranged so that 2A and 1B are reversed.  Then the sheet only needs a single pass.  By embedding a lot of calculations a given spreadsheet can need several passes to calulate everything.  This obviously takes a heck of a lot more CPU power than a sheet that is organized in order of the way it is processed.

These two statements:

"a spreadsheet getting live updates via DDE for 50 stocks"
and
"What is the cheapest desktop I can buy"

Don't logically go together.  Shouldn't the second one be "I need the apropriate tool for this large job and don't care what it costs within reason" ?  Tracking a bunch of live stocks isn't usually a casual undertaking.  If you are a professional investor, spring for the adequate equipment from the start and save yourself any hassle a cheap computer will give.  At the face value of these statements you are being penny wise, pound foolish.

Anyone who knows care to comment on whether Excel benefits more from the deeper Athlon prefetch pipeline or the wider P4's?  Methinks the Athlon at an off the cuff guess.

OK, doing a little detective work it seems optionsmm is using a system based on a single P4HT, 3Ghz (other specs unknown):
https://www.experts-exchange.com/questions/20530696/Precise-code-order-in-Excel-VB.html

Are there any automated tools to reorder a spreadsheet the way Excel would prefer?  The CPU in question should have a decent chance at this many calculations.  Otherwise, looks like a dualie might be called for but I wouldn't do that without more info.

Thank you everyone!

I greatly aprreciate your feedback.  

I just spent $5900 on this computer a few weeks ago.  This is a beauty (3.06HT, P4PE, 1 Gig 2100 DDR ram, 3 touchscreen monitors, to enable me to manage my positions.

I have an Access / Excel hybred system on this computer.  this allows me to perfectly manage ONE stock at a time.  

The stock data for my system is generated from the Access DB.  

In order to update the stock data and get live graphs of all the positions I have (like a control panel) I have another spreadsheet that I want to have running on a different machine (basically because between the DDE, and the calculation of the spreadsheet I would like to be separated from the rest of the system)  This spreadsheet updates the access DB.

Th spreadsheet is about 1.3 GIG.  it takes forever to open but once it is open it is super fast.  The reason it is so big is because it does all calculations (Bjerksund-Stensland Option Approximation) in the cells so that it doesn't have to refererence any libraries or use code to come up with the values.
 
....................................
These two statements:

"a spreadsheet getting live updates via DDE for 50 stocks"
and
"What is the cheapest desktop I can buy"

Don't logically go together.
.......................................

when i read this i laughed my ass off. you are so right!  however i am waaay over budget on this system as it is between all the hardware and software and consulting....

i guess i am just looking to keep costs down.

So there it is. I will leave this question open for a couple days and i will give some more comment on the testing as soon as I can.

Thanks again for all your help everyone!

It sounds like as long as you go with something over say a gig, and put at least 512 meg memory in it you will probably be ok. It is not going to go super fast, but it will do the job.  I run some macro's out of excel, and my most complex that simply goes through the spread sheet a few times doing calculations take maybe 20 seconds at worst.  So it is basically going to depend on how long you can wait for this report to run.  If you can wait all day, then you can go pretty cheap.

Go with 1GB RAM, and a fast hard drive, to minimize loading time and to minimize swapping RAM to hard drive as it calculates. Other than that, you could go with a bit slower, less expensive PC than the one you just bought. Probably well under $2000, but I haven't checked prices recently.

Yes folks we have a winner!  After spending some work on the project I can create fields in the Access database for the information I need to pull out from the DDE.  I can have this part running on a second machine.  Then I can have the calculations running on third machine.  I guess I will have to buy two machines, but by splitting the process in two I can buy lower end machines (sub $600) with overall better functionality of the system!

Whew!  Glad that is over.

Thanks everyone for your help!

Just so I know for next time, what additional info was needed to make this a complete answer?

I was hoping to spend around $500 or so, I hate buying expensive tech because it always comes down in price.  My $5900 setup will only be about $3000 in a year or two.  I was hoping to get the next machine cheap because I had already spent alot on the first one.  Breaking the tasks up would allow me to get two cheap computers and still have a better system than buying another monster.