Thread: Need a New Computer
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11-13-2007 08:44 PM #31
I just want to participate so I get updates on what you folks find/learn. I have a four year old Toshiba Satellite laptop which was the fastest CPU I could find then at 3.01 GHz as a monoprocessor. I use it for the Internet, WORD for writing the book and number-crunching quantum Chemistry calculations. I have run into overheating on long runs but I have a RubberMaid lap unit that I cut holes in under the PC and that helps cooling. I am worrying over a replacement unit and I am disappointed that the duo core CPUs are slower than my mono-3.01 GHz although I do see that running calculations does conflict with Internet action. I think I will look into a local company here in Virginia that makes souped up game PCs and get something fast for calculations; I don't care about super game graphics as long as I can draw still pictures. I use the laptop like a desktop but sitting in my living room recliner with the TV on in the background. The only advantage of the laptop is when I have to travel so I can take my calculations and results somewhere. I dropped a previous laptop on a gravel driveway and lost some data from the hard drive but it still ran. That means maybe the laptops are a bit sturdier in some ways. My wife has a PC which was one of the last available monoprocessor Pentiums but with VISTA. In our effort to put our main program on a CD in the book we found our program (Visual Basic V5 + WATCOM f77 code) would run on Windows 98, Windows Millennium, Windows XP Home and Windows XP Pro but choked on WINDOWS Vista (at first). Then we found that VISTA is downward compatible to a large extent if you go to the trouble to release a LOT of permissions, so that we now can run our same program(s) on VISTA as well, but it is more complicated to use VISTA. My preliminary interpretation is that VISTA has too many security restrictions and that makes it more complicated. I am interested to learn what you folks find/recommend and inparticular I am interested in the top speed in floating point arithmetic. For the nostalgia buffs with Commodore 64s we gave ours away long ago but I do have (somewhere) a Sinclair with the extra 16K memory, wow!
Don Shillady
Retired Scioentist/teen rodderLast edited by Don Shillady; 11-13-2007 at 08:47 PM.
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11-13-2007 08:49 PM #32
I know alot of people who have dealt with tigerdirect and they were not satisifed. When I built mine 2 years ago i went with newegg. They have great prices with excellent service. I have not had any problems at all. even with 2 teens surfing. I agree with everyone else about the vista problems. I like the new vista look and sounds so i put that in while still running xp media. I use my pc for general and also play streaming movies bounced to my tv with no lags. as for the asus I must have gotten a bad one. went out on me in a week. I use a gigabyte board with dual ram and surround sound. I installed a ATI radeon card for hdtv. Now my old 32" tv does not need a hdtv box as it comes through my pc.
DON there is a company near you in richmond called velocity micro that can build to your specs. They are a little pricy but they stand behind their work.Last edited by jyardgirl; 11-13-2007 at 08:54 PM.
BARB
LET THE FUN BEGIN
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11-13-2007 09:04 PM #33
jyardgirl,
Yes that is the name "Velocity Micro". As I progress possibley toward early Alzheimers it is interesting that I can still think/do equations but names come slow!
Don Shillady
Retired Scientist/teen rodder
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11-14-2007 05:39 AM #34
Denny, there is no limit to the need for speed in Quantum Chemistry computing. Before I retired I participated in some highly competitive internal politics (policy wars) always to try to get the fastest computers while an administration of non-scientists did not understand how much research depends on state-of-the-art computers. When we finally got a 32 CPU parallel system I was told I would never be able to use all the CPU-cycles of the new wonder machine but a month later they were complaining that I was hogging the computer! Actually my present laptop is faster than some mainframes I worked on back in the 80s so the answer to your question is that my next PC should exceed the 3.01GHz benchmarks in floating point arithmetic. The old LINPAK benchmarks still seem a good way to measure computational performance but for PCs there are Whetstones and Drystones and a lot of other benchmarks that depend on graphics speed but not raw number crunching. I am hoping that a game PC may be good since the graphics has to use a lot of sin(theta) and cos(theta) evaluations somewhere in calculating perspective views. Since game PCs often need to use such complicated trigonometry functions there is a good chance they will be optimized for other intensive computations. In my programs the key bottleneck is exp(x) which is used a billion billion times. Another problem is that there is a nasty problem in electronic calculations called the "two-electron-interaction" file in which one must calculate the Coulombic two-body repulsion of every electron with every other elecron and the list quickly requires huge memory resources. In my program I just dimension an array as the largest size the memory will allow and let the automatic overlay swap pieces of this large file to and from disk so I need a large cache memory and a fast disk seek time. The modern approach is to use racks of 256 or more Xeon PCs in parallel but then you need parallel software. For my use I have been pleased that my laptop can do stuff I had to use a mainframe for in the 80's so I am just looking for a fast PC with a large cache memory. I suppose a quad processor has some aspects of parallelism but the bottom line is to run benchmarks. Floating-point benchmarks are like dyno runs for an engine. You can theorize about what computer speed or engine H.P. there should be but the real test is to run a test program or a dyno run. The folks here are very knowledgable so I am listening but I would spec a PC on floating-point benchmarks and cache memory size. Maybe 64 bit PCs are the next wave? Unfortunately my programs use the WATCOM fortran-77 compiler which only treats 32 bit code. I think the 64 bit machines will run 32 bit code but eventually I would need a 64 bit compiler. I may visit Victory Micro and take my programs on a CD for an actual test on my special code. Maybe we could switch this thread a bit to a discussion of engine simulation software? What is the best LOW PRICE engine software?
Don Shillady
Retired Scientist/teen rodderLast edited by Don Shillady; 11-14-2007 at 06:00 AM.
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11-14-2007 09:37 AM #35
And to think I started this thread because I feel I need a new PC for internet browsing, saving and fixing a few pictures and maybe a spread sheet or several and have it operate all day without a 'Runtime error 605' or something similar.Dave W
I am now gone from this forum for now - finally have pulled the plug
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11-14-2007 09:49 AM #36
Dave, just go buy yourself one of the new Intel based core 2 duo's or the new quad core at the best possible price. It will undoubtably come with all of the niceties that you want including burners, biggie fixed disks, network stuff and plenty of usb ports. Today you can get cheap what would cost you your retirement savings just ten years ago.
If you don't need a monitor, get a system without one cheaper. Or if you need one, get one of the new 22 or 24 inch wide screens. I just upgraded my desktop at home with a new 22 ws for about $200. Helps these old eyes from getting worse.
You don't really need a super PC to get email and surf the net. You might if you are into doing working with the SETI institute on the side.Bob
A good friend will come and bail you out of jail....but a true friend will be sitting next to you saying..."Damn....that was fun!
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11-14-2007 10:08 AM #37
Originally Posted by mopar34
There is probably a 90% chance that is what I'll do for my new PC. But, I still want to try to spec out a homebuilt and compare. If it ends up too much of my pension bucks for a middle of the road version, then back to the store bought
Now for Don...... That's a whole new world of PCs that I have no need .Dave W
I am now gone from this forum for now - finally have pulled the plug
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11-14-2007 11:31 AM #38
Originally Posted by DennyWLast edited by IC2; 11-14-2007 at 11:36 AM.
Dave W
I am now gone from this forum for now - finally have pulled the plug
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11-14-2007 12:53 PM #39
Originally Posted by IC2
tom
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11-14-2007 02:59 PM #40
Just for the record, I checked out Velocity Micro which is indeed near my home in Southside Richmond. They only offer two laptops but interestingly the lower priced C90 with a base price of $1495 can be upgraded with a faster CPU for another $165 and that looks interesting to me. They also offer a super graphics laptop for about $2500 but that does not interest me. Their desktop PCs are generally higher priced but offer top end performance. I had a home-brew PC that started out as an XT and was upgraded through three CPUs on the same motherboard eventually with an overclocked AMD chip set that was compatible with the mother board. Overclocking can lead to overheating and reduced life so it eventually just fried! I ran one hard drive so long that I had to insert a cardboard wedge under one side to get it to turn on a different bearing surface! That kind of stuff is fun but when I got to the book I had to have reliability so I went with a Toshiba Satellite which I am still using.
http://www.velocitymicro.com/
Don Shillady
Retired Scientist/teen rodderLast edited by Don Shillady; 11-14-2007 at 03:11 PM.
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11-14-2007 04:34 PM #41
Originally Posted by jyardgirl
cards and a DVD RW thru Tiger direct and cooling fans. I bought my computer as a barebones through www.cpusolutions.com which in my book, there a great company but they have gotten expensive... I only do phone orders, maby that's why I get good service from Tiger direct IDK. In a week or so I will buy the barebones I put a link to as I cannot buy the parts individual for that. I'll let everybody kno how it goes.You don't know what you've got til it's gone
Matt's 1951 Chevy Fleetline- Driver
1967 Ford Falcon- Sold
1930's styled hand built ratrod project
1974 Volkswagen Super Beetle Wolfsburg Edition- sold
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11-14-2007 04:45 PM #42
Originally Posted by Don Shillady
here is what I would suggest. get a AMD athalon X2 5300 or better, I don't know the exact speed but I know it's over 3.0 GHZ per core.. if you built a computer or had 1 built you could find a dual prosessor board and run dual of that prosessor, and link each prosessor togther as 1 prosessor ( dual core is primaraly used for multi tasking ) and use 1 prosessor per task. I think 6GHZ would do what you need but if you needed more, you could link the second prosessor on the same task w/ extra programs for 12ghz.. that should do.
Maby even look into buying a quad prosessor HP Compaq Proliant server, a desktop version, not a rack mount or anything hotswapable that just adds cost.You don't know what you've got til it's gone
Matt's 1951 Chevy Fleetline- Driver
1967 Ford Falcon- Sold
1930's styled hand built ratrod project
1974 Volkswagen Super Beetle Wolfsburg Edition- sold
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11-15-2007 05:59 AM #43
Matt, you and Denny have aluded to a question I put to the tech guy at Velocity Micro who gave an unsatisfactory reply. That is, does the Duo or Quad hardware actually do parallel processing? My understanding of parallel processing usually requires special software to break up tasks into separate parts for each CPU and then needs a high speed cable to connect the CPUs. However a Duo or Quad chip has the CPU on the same chip so communication between them should be as fast as is possible with that close connection. If there is actual parallel computing then a Quad-CPU is obviously what I want. Thanks for the suggestion to look at other vendors. For all the hype surrounding Velocity Micro, the guy I talked to did not seem on top of the total picture. I used to get PC Week and reveled in the info when I was a consultant for a PC startup company, but they cancelled my subscription for some reason and I am now at least 7 years out of date in the PC world; such a time lag corresponds to hundreds of years in human history so I need to read more on the multi-CPU capabilities. Maybe you can answer a question? My Toshiba Satellite says it is a "ACPI Multiprocessor" under the System Hardware, but when I do Cntrl-Alt-Del I only get one task report as if there is only one CPU. I believe the CPU is a Pentium but do not know further specs on the CPU, maybe I need to "lift the hood" and see what is on there? Maybe there is some actual hardware parallel processing in the Quad-CPU? If so, I want one!
By the way, what is the best low priced engine software?
Don Shillady
Retired Scientist/teen rodderLast edited by Don Shillady; 11-15-2007 at 06:11 AM.
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11-15-2007 09:30 AM #44
Denny,
I just did a quick skim and it looks real interesting and an easy read - and have bookmarked for when I have some more time
(I'm doing some touch up painting now - "burned" thru a door jamb with 1500 - guess I got a bit too aggressive trying to get the peel out )Dave W
I am now gone from this forum for now - finally have pulled the plug
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11-15-2007 12:22 PM #45
I am considering a MAC. When they first came out the University was all over them and we adopted them. Then 'nobody' was writing engineering software for them and we dropped them and went 'PC'.
Now the MACs are running the same processors as the PC's and have the operating system with 'Boot Camp' that allows you to boot the machine in either MAC or Windows. It runs Windows at native speeds also. I have played with one and it looks really good to me; you can have the best of both worlds. But they are fairly expensive .................
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