Laptops, Batteries, and Prime95

Uncwilly · 2004-12-19, 03:08

Well, I got myself a new laptop (the 486-66 hasn't died yet...) and I am wondering about a few things.

1) If I keep it on a nice surface to keep it vented, I should be able to run P95 while it is plugged in. It's a Viao K35 running a Pent M @ 3.02
Will cooling be a huge issue?

2) I get different info from different folks. Would leaving it plugged in and running p95 for a week at a strech shorten the battery life span (I am talking total time until i must replace the batt.)?
To the best of my knowledge the batts are rated to a number of cycles.
Should I cyle the batt. once every week or two, even if I am not needing to use it "in the field"?

3) Any other issues?

Xyzzy · 2004-12-19, 11:42

A Pentium M at 3GHz?

Personally, I know of several laptops that have failed running Prime95... One of them was my wife's... The heat was too much and it ruined the HD...

There is a throttle option though... Look in undoc.txt for more info...

If the laptop is plugged in, the battery shouldn't be used...

I never cycle batteries... The newer ones aren't affected by "memory" like the old ones were...

That said, I expect to lose battery capacity based on time, even if the battery is rarely used... I expect to lose 20% per year at least... I recommend to the people I set up with laptops to buy a new battery every 2-3 years, even if the laptop is being used as a desktop...

Edit: You have a Mobile Pentium 4 processor at 3.06GHz, not a Pentium M... Be aware that CPU is going to run a lot hotter than a Pentium M would...

Edit2: And it is a Prescott! 88W!

http://processorfinder.intel.com/scr...ALL&CorSpd=ALL

Note that max temp is 75C... That is very low IMO...

Note how the fastest Pentium M uses only 21W and is rated to 100C:

http://processorfinder.intel.com/scr...ALL&CorSpd=ALL

Axel Fox · 2004-12-19, 18:18

One thing I would like to add is that laptops (and especially P4's) have a pretty intensive venting set-up, which usually also attracts a lot of dust. In my laptop, it worked fine the first few months, but then I noticed that the iteration times were higher, because the CPU throttled constantly because it was too warm.

The problem was dust, the CPU didn't cool down efficiently enough to maintain maximum speed all the time. So what I recommend (and what solved my problem) is a can of compressed air and blow it through the ventilation holes once every week or so, to keep the CPU dust free.

Mystwalker · 2004-12-20, 15:28

Quote:

Originally Posted by Uncwilly

2) I get different info from different folks. Would leaving it plugged in and running p95 for a week at a strech shorten the battery life span (I am talking total time until i must replace the batt.)?
To the best of my knowledge the batts are rated to a number of cycles.
Should I cyle the batt. once every week or two, even if I am not needing to use it "in the field"?

The power requirements are no problem AFAIK. So the battery can serve as a UPS in case of power outages.
The only battery-related issue I know of is heat - the capacity drops faster the warmer the battery is. Normally, the temperature (of the battery) is around 20°C --> room temperature. With my IBM R50P and 1,7 GHz Pentium M, I currently have 27°C with full CPU utilization for hours. With a bad surface, battery temp. goes a little above 30°C.

Badly designed notebooks usually have their batteries nearer to the "temperature generators" (a.k.a. CPU, Video, HDD, maybe Heatsink/Ventilation system), so battery temperature will rise higher - especially with processors consuming more power.

Quote:

3) Any other issues?

Noise can be a problem as well. When your CPU is a Mobile P4-m, it should be ok for idle or office use. Otherwise, the fan will start - maybe it's quite quiet, maybe not...

Paulie · 2004-12-20, 19:50

You will eventually have a heat related failure. I ran my IBM T30 (P4-M 1.7) 24/7 for 6 months, using the fan output to keep my coffee warm all morning.

One day, the memory wasn't detected anymore

: Memory was fine, needed a new mainboard.

Old memory worked fine, ran it for another couple months until I got an upgrade to a T41 (P-M 1.7) Don't run Prime on this machine for two reasons, 1) it's slower, and 2) I don't work in a lockable room anymore, now in cube'ville, so it comes home with me at night.

Make sure the machine doesn't lie flat on the bottom, it needs to be tilted to have that extra heat radiated from the casing.

E_tron · 2004-12-21, 04:18

My friends Duron based notebook suffers from Prime95 related heat. To prevent overheats, i suggested to keep the notebook vertical with the case vent up when he wasn't using it. The passive cooling helps alot.

Uncwilly · 2004-12-21, 08:06

Quote:

Originally Posted by Xyzzy

There is a throttle option though... Look in undoc.txt for more info...

Gotta d/l a new P95 package, as I have just updated the .exe in the past and v22 undoc.txt did not seem to have anything on throttling.

Luigi's factor3_2 prog really got the fan spinning.

I had the batt fully charge and unplugged it and it took it down into the 80% range in a fairly quick time.

ET_ · 2004-12-21, 08:13

Quote:

Originally Posted by Uncwilly

Luigi's factor3_2 prog really got the fan spinning.

I had the batt fully charge and unplugged it and it took it down into the 80% range in a fairly quick time.

And you still didn't try my (probably faster) alpha version 3.3

Luigi

nomadicus · 2004-12-21, 17:02

> "Make sure the machine doesn't lie flat on the bottom, it needs to be tilted to have that extra heat radiated from the casing."

Yes. Air flow and tilting it is important.
I've had very few problems with laptops. Me and the kids have 3 Dells. Combined total of roughly 80 P90 CPU years so far. I tortured one of them in a car trip; worked fine as long as air flow was good.

patrik · 2004-12-22, 10:56

My Dell Inspiron 500m (Pentium-M 1500 MHz) died after 11 months of more or less continuously running Prime95. (Sometimes I turned if off at night, due to the noise, when I was using it in my bedroom.) Luckily the warranty lasted 12 months, so I got the motherboard replaced at no cost. The cause, as diagnosed by Dell, was "wrong battery". (It was the one that came with the computer though.) So I suspect the constant heating as the problem. I don't run Prime95 on it anymore.

2004-12-19, 03:08	#1
Uncwilly 6809 > 6502 """"""""""""""""""" Aug 2003 101×103 Posts 2³·1,171 Posts	Laptops, Batteries, and Prime95 Well, I got myself a new laptop (the 486-66 hasn't died yet...) and I am wondering about a few things. 1) If I keep it on a nice surface to keep it vented, I should be able to run P95 while it is plugged in. It's a Viao K35 running a Pent M @ 3.02 Will cooling be a huge issue? 2) I get different info from different folks. Would leaving it plugged in and running p95 for a week at a strech shorten the battery life span (I am talking total time until i must replace the batt.)? To the best of my knowledge the batts are rated to a number of cycles. Should I cyle the batt. once every week or two, even if I am not needing to use it "in the field"? 3) Any other issues?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
1000 core chip that runs on AA batteries!	tServo	Hardware	12	2016-06-22 22:04
Capicitor batteries.	mfgoode	Science & Technology	14	2006-07-03 15:48

2004-12-19, 11:42	#2
Xyzzy "Mike" Aug 2002 3²·887 Posts	A Pentium M at 3GHz? Personally, I know of several laptops that have failed running Prime95... One of them was my wife's... The heat was too much and it ruined the HD... There is a throttle option though... Look in undoc.txt for more info... If the laptop is plugged in, the battery shouldn't be used... I never cycle batteries... The newer ones aren't affected by "memory" like the old ones were... That said, I expect to lose battery capacity based on time, even if the battery is rarely used... I expect to lose 20% per year at least... I recommend to the people I set up with laptops to buy a new battery every 2-3 years, even if the laptop is being used as a desktop... Edit: You have a Mobile Pentium 4 processor at 3.06GHz, not a Pentium M... Be aware that CPU is going to run a lot hotter than a Pentium M would... Edit2: And it is a Prescott! 88W! http://processorfinder.intel.com/scr...ALL&CorSpd=ALL Note that max temp is 75C... That is very low IMO... Note how the fastest Pentium M uses only 21W and is rated to 100C: http://processorfinder.intel.com/scr...ALL&CorSpd=ALL

2004-12-19, 18:18	#3
Axel Fox May 2003 96₁₀ Posts	One thing I would like to add is that laptops (and especially P4's) have a pretty intensive venting set-up, which usually also attracts a lot of dust. In my laptop, it worked fine the first few months, but then I noticed that the iteration times were higher, because the CPU throttled constantly because it was too warm. The problem was dust, the CPU didn't cool down efficiently enough to maintain maximum speed all the time. So what I recommend (and what solved my problem) is a can of compressed air and blow it through the ventilation holes once every week or so, to keep the CPU dust free.

2004-12-20, 19:50	#5
Paulie Aug 2002 223 Posts	You will eventually have a heat related failure. I ran my IBM T30 (P4-M 1.7) 24/7 for 6 months, using the fan output to keep my coffee warm all morning. One day, the memory wasn't detected anymore : Memory was fine, needed a new mainboard. Old memory worked fine, ran it for another couple months until I got an upgrade to a T41 (P-M 1.7) Don't run Prime on this machine for two reasons, 1) it's slower, and 2) I don't work in a lockable room anymore, now in cube'ville, so it comes home with me at night. Make sure the machine doesn't lie flat on the bottom, it needs to be tilted to have that extra heat radiated from the casing.

2004-12-21, 04:18	#6
E_tron Sep 2002 Austin, TX 3×11×17 Posts	My friends Duron based notebook suffers from Prime95 related heat. To prevent overheats, i suggested to keep the notebook vertical with the case vent up when he wasn't using it. The passive cooling helps alot.

2004-12-21, 17:02	#9
nomadicus Jan 2003 North Carolina 2·3·41 Posts	> "Make sure the machine doesn't lie flat on the bottom, it needs to be tilted to have that extra heat radiated from the casing." Yes. Air flow and tilting it is important. I've had very few problems with laptops. Me and the kids have 3 Dells. Combined total of roughly 80 P90 CPU years so far. I tortured one of them in a car trip; worked fine as long as air flow was good.

2004-12-22, 10:56	#10
patrik "Patrik Johansson" Aug 2002 Uppsala, Sweden 5²·17 Posts	My Dell Inspiron 500m (Pentium-M 1500 MHz) died after 11 months of more or less continuously running Prime95. (Sometimes I turned if off at night, due to the noise, when I was using it in my bedroom.) Luckily the warranty lasted 12 months, so I got the motherboard replaced at no cost. The cause, as diagnosed by Dell, was "wrong battery". (It was the one that came with the computer though.) So I suspect the constant heating as the problem. I don't run Prime95 on it anymore.