Sempron 64 2800+ overclock

[hurtstotalktoyou]

UPDATE: Prime95 failed at 1.54v and 2.4 GHz. Could that have been the fault of a new BIOS being flashed?

I have raised the voltage to 1.62, so let's hope that passes.

 

[FDF12389]

Speedfan is a good way to monitor temps in windows, there are alot of other programs for that too. (Google it yourself I dont feel like it right now) I wouldnt ever let my chip get hotter than 50* C.

 

[SynthDude2001]

My CPU generally gets to 60-63C at full load depending on ambient temps, and that's about as hot as I'd ever want it to get normally.

If you currently don't have any case ventilation at all, just adding that will likely help.

 

[t3h l337 n3wb]

Add at least an 80mm exhaust and 80mm intake fan, preferably 2 120mm fans. If that still doesn't work, lower your overclock, or stick on an XP-90.

 

[Xonoahbin]

Your processor won't die until you reach very high temps around 80.. you never really want to go over 70.. anywhere under 70 is fine if you don't need your processor to last more than about three years..

 

[Powermoloch]

you need good ventilation, it does wonders !

 

[mindwreck]

yeah that should be fine. you can use motherboard monitor on that board. I use it to monitor the temps. Or you can use the epox program and display the temperature on the post LEDs thing.
epox unified system diagnostic manager

 

[hurtstotalktoyou]

Okay, my case does seem to have spaces for two fans on the back. They're right on top of eachother, but I should theoretically be able to install an intake and an exhaust fan.

Are case fans one-size-fits-all? Or do I need to get a specific size for my case? How do I know what that size is?

Can I get an official word on that 70 figure? Is there some AMD page which will tell me that 70^C is safe?

Thanks, guys!

 

[t3h l337 n3wb]

Nonono, that's not good. You want the intake in the front or side, and the exhaust in the back. You won't really get much air circulation with both fans in the back.

 

[AkumaX]

is the heatsink hot? maybe your mobo is over-reporting

 

[mindwreck]

it shouldn't be. I have that motherboard and it gives pretty good readings.

 

[deadken]

A little off topic, but could you explain what a "Sempron 64" is? I want to do some research to see what temps others are getting, but that '64' is confusing me.

Aren't all Semprons 32bit?

 

[t3h l337 n3wb]

Some of the newest Semprons are 64-bit. Anandtech has an article about them I believe.

 

[hurtstotalktoyou]

Originally posted by: mindwreck
it shouldn't be. I have that motherboard and it gives pretty good readings.

That reminds me, do you use one DIMM or two? From what I hear, the vast majority of DIMMs are double-sided, and the 8KDA3J only accepts three sides (two double-sided DIMMs being four sides). Can that problem be fixed with a BIOS update?

 

[hurtstotalktoyou]

I keep getting conflicting reports about this issue. One person tells me not to go about 50^C, another 63^C. One other fellow says 70^C (leaving 10^C breathing room for the true maximum of 80^C). This article has a Sempron 3100+ running at 79^C safely, although the author says something about not letting it run that hot for too terribly long. Other forums have the same inconsistencies. Here, someone claims anything above 60^C is "unstable."

I can't find any official word from AMD. So, what's the true answer to my question? Should I back off my 65^C overclock? I really don't want to, but more than that I don't want to kill my CPU and/or motherboard.

 

[deadken]

Originally posted by: hurtstotalktoyou
..... A couple days ago I found time to run Prime95. While the results themselves seem to indicate a stable overclock... I'm having a problem with heat. Prime95 bumps the CPU all the way up to about 65^C, which is significantly higher than its stock speed idle temp of 40-45^C....

..... I'm going to buy an ~$8 case fan (right now it has none)..... in the mean time, I'm still running at upwards of 65^C, and I'm very concerned.

On a side note, is there some way to monitor the CPU temperature from Windows (as opposed to the BIOS)?....

I would certainly install some fans in the case. Relying on the PS Fan for airflow is a bad idea. As others have mentioned, intake from the bottom front and exhaust from the upper rear generally provides the best results.

I wouldn't consider a P95 temp to be what your system will normally be running at. P95 will most likely give you a higher temp then any other 'typical' load you put on your PC. Worry more about what the average temp you run at is then the max temp given by P95.

You should be able to find a monitoring program (like Motherboard Monitor) to monitor your temps from inside Windows with a Google search (maybe 'Speed Fan'?). If you really are monitoring from BIOS, your temps are probably a bit higher since they would drop a degree or three while you shut down and rebooted.

 

[mindwreck]

Originally posted by: hurtstotalktoyou

Originally posted by: mindwreck
it shouldn't be. I have that motherboard and it gives pretty good readings.

That reminds me, do you use one DIMM or two? From what I hear, the vast majority of DIMMs are double-sided, and the 8KDA3J only accepts three sides (two double-sided DIMMs being four sides). Can that problem be fixed with a BIOS update?

It will work with 4 sides, but it requires the memory to drop below 166mhz. If i ran it above 166 it would give me P95 errors. Never looked into the bios updates, you do lose some bandwidth but i don't notice any performance lost.

Some people have been able to run 2 sticks and maintain full speed. don't really know why, i guess some boards allow it

 

[FDF12389]

The only reason I said 50* is because without proper circulation anything above 50* can cause damage to other components if you leave your PC running alot.

 

[Xonoahbin]

Buddy, my processor at home runs 65 C idle and about 69 under load. It's lasted two years so I wouldn't be too worried. I keep my bios set to shut down systems if I go over 70 C, and it almost never happens. My voltage is pretty high and I don't have much case cooling. Yours is probably a little different in the cooling and voltage.. I'm running a Duron as it says in my sig.. Semprons are pretty close to Durons in their ability to climb to high temp peaks. Anything under 70 and your processor should be fine. Anything over 70 you're gonna not wanna do often if at all.

 

[hurtstotalktoyou]

I installed that Epox beta utility, and it tells me my CPU temp climbs to 67^C when running Prime95. I ran it for about an hour each under two settings, and both times got 67^C, but no higher.

However, my apartment is not always this cool. Sometimes it can get 10-15^F hotter, and so my CPU could conceivably reach temps slightly past 70^C running Prime95.

The good news is that Prime95 seems to be the only program that pushes my CPU that far. I'm running some intensive video conversion right now, and my CPU has remained at a solid 60^C for the past two hours.

Thanks for all the comments, guys! You've been a big help!

EDIT: I have another question, though. Installing that Epox beta utility revealed my true VCORE, which fluctuates from 1.60-1.63v. I have my BIOS set to "+0.10v." That means the default voltage is 1.5v....but I thought the Sempron 2800+ was supposed to run at 1.4v. What gives?

 

[mindwreck]

yeah the board seems to overvolt. hmm thats odd i think mine is set at "+.05v" and that gives me 1.6v. AT "+.10V" i get 1.65-1.7v. o well.

For me i had to run it at 1.6v to get 2.4 ghz to be stable, so you should be fine. with 1.6v you can do about ot about 2.5xghz.

To hit 2.6ghz and up i have to give it "+.10v" and i get ~1.68v and it just pumps out too much heat. Plus thats almost .3v overvolt, which is insane.

 

[Zap]

AMD tech docs for Semprons

Not much information, indeed nothing on the newer Semprons. I did some digging around and though the information may not be relevent to the new .09 micron cores, take it for what it's worth.

70ºC operational max
125ºC THERMTRIP_L where motherboard should stop CPU operation
-55ºC to 85ºC storage temperature

Those numbers are from various AMD tech docs relating to socket 754 and socket 939 CPUs. Again, nothing specifically for the new .09 micron Semprons. Judging from these numbers and assuming temperature is reported correctly, I'd say 70ºC and under is fine. I wouldn't go over 85ºC for any reason.

As for voltages, both AMD and Intel usually rates CPUs at a particular voltage ±10%, which is why most people say 10% overvolt is fine. I say more is usually fine since in my experience most (not all) motherboards undervolt the CPU. How much more depends on how much your motherboard undervolts (and if it is reported correctly).

 

[hurtstotalktoyou]

Well, I ran Prime95 for eight hours with no errors, so I'm assuming I'm fine, there. The power is still 1.6-1.63v, but I suppose that will have to do. I don't see any reason to lower the voltage, considering the CPU is running just fine, and at a max of ~67^C, 3 degrees less than the AMD-sanctioned 70^C. And usually it's closer to 55^C.

 

[Zap]

You may want to try lowering voltage because voltage=heat, plus 1.6v+ is a lot for a .09 micron core. Many people have had good luck with just a tiny bump in voltage, so you can probably lower voltage while keeping the overclock/stability. If the default is 1.4v, try something in-between such as 1.5v and run Prime to test for temperatures and stability.

My A64 2800+ (default 1.8GHz) runs at 2.4GHz on my Epox EP-8KDA3I board at default voltage.

 

[Brunnis]

I was just about to say that those temps were awfully high for a Sempron, even when overclocked to 2.4GHz. That increased voltage pretty much explains it all, though. My brother just got a 64-bit Sempron 2800+ too and it's very cool so far. The highest I've seen it become during Prime95 is 40C. That is when overclocked to 2GHz. He has an ASUS K8N, though, and that mobo gives the CPU the 1.4V it is rated for.

I'm going to try to push it to 2.2GHz in the coming days. Should be easily done on stock voltage.