Sager NP4750 cpu voltage mods and temps results Review

Athlon64 3400+ DTR used for test. Max multiplier of 11 (2200Mhz) used.
1.03 BIOS
AC Power

CrystalCPUID 4.0.0.214 used to modify default voltage tables.
"Multiplier Management" feature enabled.
Tested voltages of 1.5 through 1.3 in .025 increments.

Verified desired voltage was obtained using ClockGen for VIA K8T800 (ICS950405) and AMD PowerNow! Dashboard
MobileMeter 0.3.1.0 used to obtain temps. (2 sec update interval)

Tested with Passmark BurnIn Test V4.0 Pro - following tests performed:
CPU - Maths - 100%
CPU - MMX / SSE - 100%
Memory (RAM) - 100%
2D Graphics - 50%
3D Graphics - 50%
Disk C: - 50%
Network - 50%


All reported temps are in Celcius.
10 Minutes testing intervals. All tests started with CPU at 40.
Room temp 27 (Ceiling fan running, but not directly overhead)
Power Scheme - "Always On"

Notebook rear elevated for increased airflow. (Used Doom3 CD Case)
1.500v - 65-66c
1.475v - 63-64c
1.450v - 61-62c
1.425v - 60-61c
1.400v - 58-59c
1.375v - 57-58c
1.350v - 56-57c
1.325v - 55-56c
1.300v - 54-55c * Starts to fail CPU-MMX/SSE test
1.275v or lower hangs notebook

Notebook laying on flat surface tests.
I decided not to run all voltage combinations. Just the high, low and middle.

1.500v - 69-70c
1.400v - 61-62c
1.325v - 57-58c

Additional information:
Sound Measurements taken with RadioShack Sound Level Meter.
Set to "Fast Response", "A Weighting"
Measurements taken during BurnIn Test run at 100% fan speed.

Fan noise in Dec. 1" from case, measured directly in middle

Right side - 58dbl
Left side - 60dbl
J,N,M key cluster - 55dbl


HDD temps 47-48 recorded during testing.

Results analysis:

Ensuring that the underside of the notebook has adequate airflow will diminish temps by 4-5c. Lowering the default voltage from 1.5 to 1.4 volts will diminish temps by 8-9c.

Interesting enough, the lowest stable voltage that I obtained of 1.325 performs within 1-2c whether or not the notebook is elevated. This is due to the fact that the temp that the CPU produces at this voltage is easily handled by the internal cooling system without additional airflow.

I now use CrystalCPUID4 to manage my multipliers dynamically with my top voltage set to 1.325. I am now experiencing a 15-16c drop in temperature compared to the stock settings.

I am now much happier with my Sager NB4750, especially when used as a "Laptop". I highly suggest that NP4750 owners experiement with lowering the voltage of their CPU in order to get a handle on the high temps.

I am now in the process of testing voltage ranges when the notebook is running at 800Mhz and 1800Mhz. After releasing these findings, I will investigate power saving when running on a battery using my new default voltages.

I hope you find this information useful.

NetMavrik

Additional testing at 800Mhz

Temperature results for various voltages at 800Mhz.
800Mhz Maximum speed. (Capped with CrystalCPUID4)
Desired voltages verified with AMD PowerNow! Dashboard.
Temps were measured with MobileMeter.

Passmark BurnInTest V4.0 Pro used to test CPU at load.
Only CPU tests were performed. Default values of 50% for the test runs.
BurnIn test were ran for 5 minutes only. No higher temps observed for longer test runs.
5 minute cool down between test runs. No lower temps observed for longer cooling periods.

Notebook laying on flat surface tests.
Stock voltage is 1.100 volts at 800Mhz

1.100v - 41c idle, 43-44c under load
1.000v - 40c idle, 41-42c under load
0.900v - 39c idle, 40-41c under load
0.800v - 37c idle, 38-39c under load

Hard disk drive temperature was observed at 43c for the duration of the tests.
Both Wifi and Bluetooth were enabled.

NetMavrik

My new P-State tables for my 4750

Just to recap, the stock setup for the Sager NB4750 3400+ DTR is as follows:

Max P-State is 2200Mhz at 1.500 volts
Mid P-State is 1800Mhz at 1.300 volts
Min P-State is 800Mhz at 1.100 volts

After carefull testing and analysis of the above data I posted earlier, I have adjusted my setup as follows:

Max P-State - 2200Mhz (11x multi) at 1.325 volts
Mid P-State - 1500Mhz (7.5x multi) at 1.100 volts
Min P-State - 800Mhz (4x multi) at 0.800 volts

I also adjusted the minimum time to spend at the Max P-State down from 5 seconds to 3.

For those of you that want to atempt this, remember that your system will freeze up when the cpu is too deprived of voltage. As with any lockup, your file system or registry could become corrupt. Other than that, no physical harm can come from undervolting a component. It just may simply not work at the voltage that you try to set it at. Take care not to have CrystalCPUID run at startup and apply the new voltage tables unless you are sure that they work 100% for your cpu.

NetMavrik

CrystalCPUID screenshot

Hey Ogre.

Where can I post a screenshot of the settings I am using for CrystalCPUID?

I've made alot of small tweaks that can save your hours, if they will work for you.

Duh

I figured it out. Attached is screenshot of the settings I am currently using in CrystalCPUID. Make sure that you have the latest CPU driver from AMD or Sager (they are the same). Here are the startup settings you need to add to the CrystalCPUID shortcut to make it activate the new voltage tables.

"C:\Program Files\CPU Utils\CrystalCPUID40\CrystalCPUID.exe" /CQ /HIDE

Lastly, set the Power Scheme to "Always On". This allows the new settings to take over. The other settings perform dynamic throttling using the default BIOS voltages. If you don't use the "Always On" power scheme, the BIOS defaults will eventually overide your custom ones.

NetMavrik

HDD Temps

O, I am working on cooling the hdd too, but the solution requires a drill! Seriously!

NetMavrik

Well, if I do decide to mod it, it will have to be transparent. No new fan or holes on the exterior. The current solution I am working with right now involves removing the plastic plug from the pc card slot, and using that "hole" for an intake. I will go into more detail later, if it is at all feasible.

NetMavrik

mayaman2

What results? You mean the temps I am experiencing at these new voltage settings?

Overnight BurnIn Test Pics

Here is a screenshot of my desktop with BurnIn Test running for over 7 hours. The PowerNow application is visible so you can see the current voltage I am running. MobileMeter is running in graph mode at the bottom right. Check out those temps! The room temp was a constant 25c.

The results I posted on Sat were with the stock heatsink setup from Sager. These results are after an application of Geil 5% silver and 5% copper thermal paste. I noticed 2-3c drops across the board after doing that.

For those who don't open the attached pic, Mobile Meter showed temps from 51-53c, 52c being average. This is with the CPU and Memory being tested at 100% load. Not even Doom3 is that relentless. BurnIn Test probably doesn't load up the GPU like Doom3 will, however.

NetMavrik

No. The CPU is running at the same speed, I just determined the lowest voltage necessary for stable operation and lower temperatures.

I'm sure it would help, since my system is now around 20c cooler than it was. I would avoid placing it on the bed or couch, because of the air intakes on the bottom. Right now I am using the 4750 for surfing and email. Here is a shot of mobilemeter. Pretty cool, huh.

I have already. Last post on page 1. Zoom in a little, and MobileMeter is running bottom right, above the Clock. It averaged 52c over a 7 hour test run.