RE: Mersenne: Slow CPU's in a Proliant 2500
I just wanted to thank everyone for all the great responses I got. I have decided to just leave it alone. Perhaps at a later time I will look into putting a Celeron in here as Aaron Blosser suggested. Again, thanks to everyone! You were all very helpful. Matt _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: W2K screen saver vs. Prime95
> I just up(?)graded from NT4 to Win2000. In the old NT4 screen > saver selections was a "Blank Screen" option that I used. It > would blank the screen when it locked my keyboard but it didn't > run any active screen program that would take cycles from > Prime95. Under W2K I don't have any Blank Screen option. If I > want the screen saver active to lock the unattended keyboard I > have to pick one of their 'active' display selections. > > Any ideas on how I can get automatic keyboad lockup with a blank > (or cleared) screen AND leave the most cycles for Prime95? You should see a screen saver called 'Default Screen Saver' That's what you want... just a blank screen. Note: If you have power saving on your monitor, once your monitor turns off, any running screen saver is "supposed to" stop running. Whether that's the case or not for many screen savers, I have no idea. Besides the blank screen, another good, low impact saver is the "logon" one. Aaron _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: W2K screen saver vs. Prime95
I just up(?)graded from NT4 to Win2000. In the old NT4 screen saver selections was a "Blank Screen" option that I used. It would blank the screen when it locked my keyboard but it didn't run any active screen program that would take cycles from Prime95. Under W2K I don't have any Blank Screen option. If I want the screen saver active to lock the unattended keyboard I have to pick one of their 'active' display selections. Any ideas on how I can get automatic keyboad lockup with a blank (or cleared) screen AND leave the most cycles for Prime95? Cheers... Russ _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Mersenne: OT: Distributed Computing: YETI@home
Appears that SETI@home has some new competition - YETI@home. Details (and perhaps a few chuckles) to be found at: http://www.phobe.com/yeti/index.html On a bit more serious note - humour does often try to capture what people feel uncomfortable about. I think the comments about "aggressive algorithm" that takes control of the computer probably echo the reservations many have towards participating in distributed computing. Rich Pardoe _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Slow CPU's in a Proliant 2500
> That is probably your problem. Your bus is only 66 mhz. You are not able > to access your memory as fast as you want to process the data. I once > upgraded a 486 100Mhz to a 486 150Mhz (I think, it was a while ago) and > there was almost no change in the speed. I overclocked the memory bus from > 66 to 75, and lowered the multiplier (so the CPU was at the right speed) and > gained more of an improvement. You may have to buy new, faster memory to > make this possible, but the stuff is CHEAP right now. (just bought 128MB > PC-133 Cas 2 for $30!) Good luck! the PPro chips only supported 66Mhz FSB operations, so thats going to be all the motherboards support. _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Slow CPU's in a Proliant 2500
>I have set the switches on the I/O board for 66/333 speed. > That is probably your problem. Your bus is only 66 mhz. You are not able to access your memory as fast as you want to process the data. I once upgraded a 486 100Mhz to a 486 150Mhz (I think, it was a while ago) and there was almost no change in the speed. I overclocked the memory bus from 66 to 75, and lowered the multiplier (so the CPU was at the right speed) and gained more of an improvement. You may have to buy new, faster memory to make this possible, but the stuff is CHEAP right now. (just bought 128MB PC-133 Cas 2 for $30!) Good luck! Brian Peltzer [EMAIL PROTECTED] _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Slow CPU's in a Proliant 2500
On 7 May 2001, at 2:04, Sandy Harris wrote: > Might it just be the effect of slower cache? As I recall, the numbers were: > > P Pro256 or 512K one CPU clock to deliver data > P II 512 K two > Celeron 128 K one > > and on some tasks, Celeron outperforms P II at the same clock because of > this. Though when I investigated why a C266 system I had outperformed a PII- 266 running Prime95, I found that the reason was that the LX chipset on the PII was assuming that the memory was very slow, whereas the EX chipset on the C266 system was taking advantage of the memory timing information set in the PROM on the SDRAM boardlet. > > If the process is cache-bound and key data fits in both caches, this gives > about the right numbers. P II cache runs at 333/2 which is to 200 roughly > as .448 is to .515. Key data does NOT fit in the caches. In fact if you look at the timings page you will see that where the same processor is available in "slow" 512K L2 cache & "fast" 256K L2 cache formats (e.g. PIII vs PIIIE, or Slot A Athlon vs Socket A Athlon) the "slow" 512K cache version usually runs Prime95 a few percent faster. The key is the memory bus loading and the efficiency of access to the memory. > > Alternately. do you just need a differently optimised version of the code > to get the best out of your P IIs? No, the PPro and the PII are the same hardware architecture. Regards Brian Beesley 1775*2^332181+1 is prime! (10 digits) Discovered 22-Apr-2001 _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
Re: Mersenne: Slow CPU's in a Proliant 2500
Besides other nefarious things I'm known for, I am also a Compaq ASE, so hopefully that'll carry some weight in my response. :) > > I have just upgraded a Proliant 2500 from dual PPro 200's to dual Pentium II > > 333 overdrive processors. ... > > Now before I upgraded, I was running double check's on 2 exponents, 668. > > I was getting about .515 second iteration times. > > Now that I have upgraded, I am only getting .448 second iteration times. > > Might it just be the effect of slower cache? As I recall, the numbers were: > > P Pro256 or 512K one CPU clock to deliver data > P II 512 K two > Celeron 128 K one > > and on some tasks, Celeron outperforms P II at the same clock because of > this. One problem is most likely due to the Pentium II Overdrive's cache architecture which, if I recall correctly (I hate abbreviations), runs at half-speed like the other PII's. The PPro cache ran at full speed, and the Proliant 2500 (and I've got a couple of the 2500's around) came with 512MB L2 cache chips, but could be ordered with the 1MB or 2MB L2 PPro's also... believe me, even on a 200 MHz machine, that extra cache, and running at full speed, does make a difference. Sure, a PII running at 333 would be faster, but you have to deduct "speed points" for the smaller cache (256K I think) running at half the full speed (166 MHz, even less than the cache on a PPro 200)... Also, please DO NOT DO NOT DO NOT DO NOT replace the BIOS chips on your 2500 with the E50 BIOS. There are a LOT more differences in the systemboards for a Proliant 2500 E24 (the PPro system board) and the E50 board (the PII board). Not only would those BIOS chips not work, but they would *really* not work (I'm not sure what that means...) The odd performance stemming from running NTPrime on both CPU's is a direct result of the memory architecture not being optimized for PII accesses and speeds. The E24 board was made to work great at handling mem requests for a pair of PPro's. Compaq does a GREAT job at SMP architecture, even on their older boards, using their custom chipsets and all that (much better than off-the-shelf dual CPU boards). However, when you go beyond what the motherboard was designed for, the peak performance of the mem architecture goes away. I would say that the BEST option you could come up with would be to forget the PII Overdrive chips (they're almost worthless, in my opinion, performing worse than a regular PII at the same speed... go figure. It shouldn't be that way, but that's my experience... The thing to do is to get the PPro-Celeron socket adapter from Powerleap (www.powerleap.com). They're compatible with the Proliant 2500 (and a few other dual PPro machines)... One caveat... you can get 2 upgrades for your 2500, but due to some physical constraints, some people have been forced to shave off a few millimeters of PCB to get both CPU's working in the 2500... but it can be done. Another caveat... only the older Celeron 550's are dual CPU capable... the newer ones are now missing that capability altogether. Powerleap sells kits of 2 Celeron 550's that are SMP capable, so that's one way to go. Another way to go is to forego the dual CPU and just get the fastest single Celeron they support, which is a Celeron 766MHz (the fastest 66MHz Celeron there is). Given the trade-offs of running dual 550's or a single 766, you might get better performance with the single, faster CPU than with 2 slower ones... only some benchmarks of either would really tell you though. Hmmm... I'm currently debating which way to go on that for the 2 Proliant 2500's I currently run. I'm leaning towards the single faster option for my own machine, which doesn't really need dual CPU's for much, and getting the dual 550's for the server at work since it does more things. Hey, that way I can tell you all which works better at NTPrime. :) To sum up: ... E24 boards don't work with E50 BIOS (there's actual physical differences in the board, which should be obvious since one is socket 8 and one is Slot 1. :) ... PL-Pro/II upgrades using Celeron (cache runs at full speed!) are a MUCH MUCH better option than the cheesy PII Overdrives (if you can even find one of those dinosaurs) ... Besides NTPrime, judge whether dual Celeron's at 550 would be better or worse than a single Celeron at 766. Aaron _ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
