As I've mentioned before in several postings I'm experimenting with a Low Power Mobile Sempron (25 watt max.) in a DFI UT3 Lanparty motherboard with a Zalman 7000B cooler.
I have this combo now. The mobo detects the CPU fine as a Mobile Sempron 2600 (which is actually exactly what it is). It starts the CPU with a multiplier 4, which is a bit too low, but this would be OK, if I was able to increase the multiplier. But as soon as I try to change the multiplier with CrystalCPUID the computer locks. I tried with RMCLOCK as well, but it locks too.
Any ideas?
Bye egghat.
CrystalCPUID on Low Power Mobile Sempron
Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee
time for a short update.
If I set the multiplier to 8 (which should be right for my CPU --> 1600 MHz), i can lower the multiplier to 4 with CrystalCPUID, but when I raise back to 8, the system hangs. Huh, strange.
For a moment I thought, that the Mobile Semprons don't support Cool'nQuiet after all, but lowering the multiplier works and raising doesn't?
Bye egghat.
If I set the multiplier to 8 (which should be right for my CPU --> 1600 MHz), i can lower the multiplier to 4 with CrystalCPUID, but when I raise back to 8, the system hangs. Huh, strange.
For a moment I thought, that the Mobile Semprons don't support Cool'nQuiet after all, but lowering the multiplier works and raising doesn't?
Bye egghat.
My problem still exists. I can lower the multiplier, but I can't raise the multi.
I'm from Germany, so my source may not be suitable for you: Lion Electronics.
Anybody knows what the core voltages of the Low Power Mobile Sempron 2600 + should be? Mine is booked in with 1,05 volts, which may by too high (or low?) and therefore the board crashes...
Bye egghat.
I'm from Germany, so my source may not be suitable for you: Lion Electronics.
Anybody knows what the core voltages of the Low Power Mobile Sempron 2600 + should be? Mine is booked in with 1,05 volts, which may by too high (or low?) and therefore the board crashes...
Bye egghat.
it's a mobile chip so it's definitely cool'n'quiet enabled. i'd try flashing to your board's newest bios, it sounds like it isn't doing exactly what the sempron wants during power transitions.
1.05 volts sounds a bit low too, i would've thought it'd be 1.2 or so. i'm just guessing though - the manufacturing process it's made with is fine with anywhere up to 1.4 volts, so you could try pushing it up to 1.2 in the bios and see how that alters the stability problems (if at all).
1.05 volts sounds a bit low too, i would've thought it'd be 1.2 or so. i'm just guessing though - the manufacturing process it's made with is fine with anywhere up to 1.4 volts, so you could try pushing it up to 1.2 in the bios and see how that alters the stability problems (if at all).
Haven't seen a 35 watt Low Power Mobile Sempron, but I've seen Low Power Mobile Athlon64s. They should be quite a bit faster, but (for me) were too expensive (~200 Euro , ~250 USD) to risk them for the experiment I'm doing now ...
I've checked DFI for a Bios update, but there doesn't seem to be one since October last year ... I'll write them an email.
Bye egghat.
I've checked DFI for a Bios update, but there doesn't seem to be one since October last year ... I'll write them an email.
Bye egghat.
Runs now with RMClock
Huh, very interesting forum. People who patch beta bioses ... Crazy crazy, but very helpful if you're not going with the stock voltages.
I didn't try a new bios (found a link there to DFI "official" beta bios, which I haven't found before). But I found an interesting hint over there: Enable "Registered DIMMs" for the RAM settings in RMClock. Suddenly everything seems to work fine. I'm doing a stress test now (endless loop of Pi calculation with short pauses inbetween) and see how this goes.
I'm running at 4*200 MHz @ 0.8 volt and 8*200 MHz @1.075 volt. I'll see, if I can go even lower.
I don't have Speedfan running (I'll post a separate thread about this), but I guess, that at 4*200 MHz @0.8 volt I should be able to turn of the CPU fan.
Bye egghat.
I didn't try a new bios (found a link there to DFI "official" beta bios, which I haven't found before). But I found an interesting hint over there: Enable "Registered DIMMs" for the RAM settings in RMClock. Suddenly everything seems to work fine. I'm doing a stress test now (endless loop of Pi calculation with short pauses inbetween) and see how this goes.
I'm running at 4*200 MHz @ 0.8 volt and 8*200 MHz @1.075 volt. I'll see, if I can go even lower.
I don't have Speedfan running (I'll post a separate thread about this), but I guess, that at 4*200 MHz @0.8 volt I should be able to turn of the CPU fan.
Bye egghat.
don't really know 
CPU-Z says, its a 90 nm core. Codename is Sonora., BrandID35, Family F, Model C, Stepping 0, Ext. Family F, Ext. Model 1C, Revision DH8-D0, 128 KB L2-Cache, SSE and SSE2 seem to be supported, SSE3 not.
Can't tell you more, cause AMD seems to refuse to give any more details. Full specifications are only avalaible for notebook manufacturers. I don't even know, what "normal" voltages my CPU runs on.
Bye egghat.
CPU-Z says, its a 90 nm core. Codename is Sonora., BrandID35, Family F, Model C, Stepping 0, Ext. Family F, Ext. Model 1C, Revision DH8-D0, 128 KB L2-Cache, SSE and SSE2 seem to be supported, SSE3 not.
Can't tell you more, cause AMD seems to refuse to give any more details. Full specifications are only avalaible for notebook manufacturers. I don't even know, what "normal" voltages my CPU runs on.
Bye egghat.
you have a so called "Oakville" core. Have a look at the link. It only deals with 62W TDP and Vcore of 1,40 but it should be comparable
http://forums.amd.com/index.php?showtopic=40025
Short googling found the next link. Your vcore should be 1,25V.
http://fab51.com/cpu/sempron/s30.html
One advantage of this CPU vs a undervolted Winchester is the tCase max of 95° which gives you a nice headroom.
http://forums.amd.com/index.php?showtopic=40025
Short googling found the next link. Your vcore should be 1,25V.
http://fab51.com/cpu/sempron/s30.html
One advantage of this CPU vs a undervolted Winchester is the tCase max of 95° which gives you a nice headroom.
Thanks I lot. I digged fab51, but didn't find this page.
FYI: I'm running my CPU with 1,05 volt at high speed (8*200) and 0.85 volts at low speed (4*200). So I'm undervolting rather heavily.
At low speed the CPU temperature is below 35 degrees and the CPU cooler is completely switched off. At high speed (under full load, calculating PI) the cpu fan runs at 1500 rpm and the temp is hovering around 45 degrees C. So I#m quite happy with this setup.
I'll post a longer article later.
Bye egghat.
FYI: I'm running my CPU with 1,05 volt at high speed (8*200) and 0.85 volts at low speed (4*200). So I'm undervolting rather heavily.
At low speed the CPU temperature is below 35 degrees and the CPU cooler is completely switched off. At high speed (under full load, calculating PI) the cpu fan runs at 1500 rpm and the temp is hovering around 45 degrees C. So I#m quite happy with this setup.
I'll post a longer article later.
Bye egghat.
It's time to reanimate this thread! 
I finally completed the core of my system (same CPU & Mobo as Egghat, 512MB ram, Radeon 9600 and temporary an Enermax 350w PSU) and began undervolting my Sempron. But my results are worse than his ones:
I achieved 0,9v with 800mhz and 1,125v with 1600mhz (plus 1v for 1200mhz). So my voltages are quite high compared to Egghat; when I continue to lower them, I get bluescreens.
My question is (of course!): Why are my result so mediocre? Was I just unlucky with the CPU I received (in other words: Has Egghat an excellent Sempron while mine is just regular?). Or could it be another part of my system, which prevents my cpu from undervolting any further (ram/ PSU??)
But nonetheless, I'm looking forward to use the computer as a HTPC, which would of course being even better with less heat like Egghat's pc.
I finally completed the core of my system (same CPU & Mobo as Egghat, 512MB ram, Radeon 9600 and temporary an Enermax 350w PSU) and began undervolting my Sempron. But my results are worse than his ones:
I achieved 0,9v with 800mhz and 1,125v with 1600mhz (plus 1v for 1200mhz). So my voltages are quite high compared to Egghat; when I continue to lower them, I get bluescreens.
My question is (of course!): Why are my result so mediocre? Was I just unlucky with the CPU I received (in other words: Has Egghat an excellent Sempron while mine is just regular?). Or could it be another part of my system, which prevents my cpu from undervolting any further (ram/ PSU??)
But nonetheless, I'm looking forward to use the computer as a HTPC, which would of course being even better with less heat like Egghat's pc.
Of course your voltages are a bit higher than mine, but not by that much. Remember that the normal core voltage of the Semprons is 1.4 volts, so everything under 1.2 actually is good.
When you put your bios thresholds to 30 and 40 degrees your fan should be off when the CPU is at 4*200 and should be rather slow (and quiet) even when running at full speed.
If you buy a normal CPU there's a good chance to undervolt a bit, when you're lucky, even by 0.2 or 0.3 Volts. But your chances to go really low are better when you start lower. (If read about someone in these forums who runs his normal Venice core Athlon 64 at 1.2 volts at full speed. So it's questionable if the low power mobile CPUs are worth it. It may be easier to just buy 3 normal Athlons and return the two that don't allow deep undervolting ...)
Bye egghat.
When you put your bios thresholds to 30 and 40 degrees your fan should be off when the CPU is at 4*200 and should be rather slow (and quiet) even when running at full speed.
If you buy a normal CPU there's a good chance to undervolt a bit, when you're lucky, even by 0.2 or 0.3 Volts. But your chances to go really low are better when you start lower. (If read about someone in these forums who runs his normal Venice core Athlon 64 at 1.2 volts at full speed. So it's questionable if the low power mobile CPUs are worth it. It may be easier to just buy 3 normal Athlons and return the two that don't allow deep undervolting ...)
Bye egghat.