On Saturday 08 March 2003 03:35, spike66 wrote: > Some of you hardware jockeys please give me a > clue. I have two machines at home running GIMPS 24-7. > One is a P4-2Ghz. The other is a 5 yr old 350 Mhz > PII, which is in need of a tech refresh. Clearly > there is more to computer performance than clock > speed, but for GIMPS I suppose clock speed is > everything. Is it? My other machine already has > a DVD writer, networked etc, so I need not rebuy > that. What should I buy? I have no hard spending > limit, but I am looking for value and suppose that > a thousand dollar machine would be more than > adequate. Does AMD vs Intel matter? Does bus > speed matter?
1) In this position you are _far_ better off building your own system. It's interesting in itself, offers a cash saving when you can delete unwanted parts or recycle old peripherals and is the only way you can guarantee to get optimised performance. Medium or large systems builders catering for the retail or direct sales market will almost always not be able tell you the specification of important parts of the system - in fact just about all they will be able to tell you is processor type, speed & HDD size. This is like choosing an automobile on the basis of number of cylinders, top speed & number of seats - usually there are other factors you might want to consider. 2) If you want to use the system for "general purpose" tasks then there is something to be said for AMD systems. But, because of the efficiency of SSE2 code in Prime95/mprime, a P4 system is _much_ better value for money if that's what you're intending to use the system for. 3) Whether you go for AMD or Athlon, avoid the top two or three CPU speeds. You pay increasingly large amounts of money for relatively small increases in speed. In any case, if you're building a system which is otherwise "state of the art", you will be able to upgrade the processor in one year to a processor chip faster than today's "top of the range", keep the old one and still have money in your pocket. (The old processor chip can of course be sold on eBay). 4) The chipset for P4 systems is in a state of flux at the moment. There are several available but only two worth considering: i850e and e7205. The differences here are substantial e.g. i850e supports 533 MHz RDRAM (PC1066) whereare the e7205 supports dual-channel DDRAM. Actually the theoretical memory bandwidth are the same - but DDR is much cheaper & easier to obtain. Also the e7205 chipset, and only the e7205 chipset, supports hyperthreading. Systems using single-channel DDRAM memory will be considerably slower with the same clock speed - probably 10-15%. The way I look at it, the ~$200 required to buy a 10% faster processor is better spent on a more efficient memory subsystem. Same applies with RDRAM - using "cheap" PC800 RDRAM in a system which supports PC1066 is a very bad compromise. The last two systems I've built have been as follows: P4-2533 / Asus P4T533-C / 4 x 128MB PC1066 RDRAM P4-2666 / Asus P4G8X / 2 x 256MB PC2100 DDRAM Neither of these mobos are cheap, but bear in mind that the P4G8X has just about everything you might need on board, except the graphics adapter. (6 USBv2, 2 Firewire, 6 channel audio, gigabit LAN as well as the still-standard PS/2, serial & parallel ports). It also supports RAID but only on the two serial ATA ports it boasts in addition to the two standard IDE ports. The combination I used for the P4-266 system should come in _well_ under $1000. You could probably recycle the old peripherials (monitor, kb, mouse, floppy, CD, hard disk) from your old P2-350 unless you really feel like shelling out. You _might_ be able to recycle the old case as well - however you will probably need to replace the PSU with a new one in order to supply the power requirements of a P4 system. Look for PSUs rated over 300W with dual fans - I particularly reccomend the Enermax PSU with rheostat fan speed control because it's quiet & effective, though certainly not cheap. In any event it would be worthwhile considering replacing the case with a new, top-end version in order to get decent cooling without having to have noisy fans. The Coolermaster ATC-200/201 cases are very well built, elegant and have 4 quiet fans - cooler and much quieter than one "standard" one. Thermaltake Xaser cases are cool and also feature multiple fans with a speed controller; they're significantly cheaper and undoubtedly adequate but much "tinnier" in build quality. You should also consider the Zalman CPU cooler instead of the retail Intel unit. It's very effective and very quiet (except when turned up to maximum, which shouldn't be neccessary!) Adding a Coolermaster case & Zalman fan to the suggested P4-266/P4G8X system will get you close to the $1000 mark. The last wrinkle here is that you will probably _not_ be able to recycle the graphics card from your old system. All decent P4 mobos _require_ an AGP graphics card capable of running at 1.5V; most AGP cards more than 3 or 4 years old will not run at 1.5V. Unless you are really into gaming, $100 will buy you a very decent graphics card, but do check that it will run on 1.5V. The trick here is to check the connector - if it has both slots it supports both 1.5V and 2.5V operation. Reasonably priced graphics cards known to run on the Asus boards I've reccomended include Matrox G4xx/G5xx & Connect3D Radeon 9000 DDR. The Matrox cards are now far from "state of the art" but are hard to beat for 2D performance. If you can't find a new one, try eBay. If you really do need state-of-the-art 3D gaming performance, try a different expert (I'm not up to speed), but be prepared to shell out a few hundred bucks, be aware that at least some of the fastest cards have cooling fans which are SERIOUSLY LOUD and at least consider a PSU upgrade to 450W minimum. If you feel you need a new monitor, look at 17" 1280x1024 LCD panels, which are now getting fairly reasonable in price. But the old monitor will be usable, and a KVM switch enabling you to connect _both_ your systems to the monitor on your newer system will cost a lot less than any usable new monitor. Finally, if you're running Windows on your old system & want to move your Windows license to the new system, check if the license you have is OEM or retail. If it's a retail license, no problem provided Windows is completely removed from the old system. If it's an OEM license, IANAL but you're probably breaking Uncle Bill's EULA even if you transplant the HDD on which Windows was originally supplied pre-installed. In any case you'll need to re-install to get the devices on the new mobo recognised, otherwise you won't be able to run in anything other than "safe mode". If you have only a "recovery CD" (rather than a proper installation CD) this might prove rather difficult. My advice is to play absolutely safe by dumping Windows, but I'm well aware that not everyone feels psychologically able to cut their apron strings. Those who are brave enough rarely regret making the leap of faith required to switch to linux. Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
