Where do I go from here?

Botanic · Post by **Botanic** » Thu Apr 16, 2009 12:29 pm

My main system half broke down.
I noticed that it hangs every now and then.
So I ran memtest86 on it. Memtest gives loads of errors after running only a few seconds.
I have tested different sticks of RAM in different slots to no avail.
Seems as if the mainboard is faulty, or maybe the CPU.

The CPU is an AMD Athlon(tm) 64 X2 Dual Core Processor 3800+.

Where do I go from here?
I have had no plans on getting new stuff since I have been happy with the speed of this system. I haven't looked at computer parts for more than a year. So I have no clue of what to get.

A new mainboard with an AM2 socket is hard to find today. Then again, it would suck big time if I buy a new mainboard and realise that the problem is in the CPU...
Also it wouldn't feel right to buy old "crap".

I don't want to spend loads of money on a new system, since I know that I wont need a lot of speed.
The system has to be silent. Integrated GPU will do just fine.

Any pointers are welcome.

xafier · Post by **xafier** » Thu Apr 16, 2009 1:22 pm

As far as I am aware your AM2 socket CPU will work in an AM2+ motherboard and also in an AM3 motherboard which is set for DDR2 RAM (I am ready to be corrected though)

So you could get yourself a modern motherboard, and if the CPU is buggered then you'll not have wasted money and then can consider a low end Phenom or new AMD X2 or something

hybrid2d4x4 · Post by **hybrid2d4x4** » Thu Apr 16, 2009 5:13 pm

When you say you tried "different sticks", are those ones known for sure to be good? If they're something you had laying around unused for a long time, maybe check them in another system or borrow a stick from a currently running computer to be sure. If you get the error on a known good stick of RAM, as you said it could be either the board or the CPU. Since Athlons have the memory controller on the CPU (unlike all but the latest Intels, which have it in the chipset), I'd lean a bit more in that direction (though it might be possible that the problem might be something like a short in the pathways between the CPU and RAM slots). Obviously, if you have access to a known good CPU to try, do it to make sure. Also try taking the board out of the case and run the test on a bench if you want to rule out the motherboard shorting (though that's probably grasping at straws).

Unless someone chimes in with some other troubleshooting ideas, if I were you, I'd probably replace the CPU first (anything between the 4050e and 5400+ will do, but if you care about saving a few watts the 4050e/4450e/4850e or 5050e may interest you despite their higher cost/clock speed). Avoid the 7750 and other 1st gen Phenoms. My reasoning is that the CPU is the cheaper part to swap, so if you don't know which part is causing it, replacing the cheaper part is a smaller gamble.
If that fails, like xafier says, any AM2+ motherboard will do (although I'm pretty sure AM3 won't, since they use DDR3 and only the new AM3 Phenom IIs have memory controllers that work both ways). If you care about High Definition video, the 780G or GeForce 8200/8300 based boards are best, otherwise the 740G, 690G or 760G will probably save you some money.

K.Murx · Post by **K.Murx** » Thu Apr 16, 2009 10:06 pm

Ifyou live in an urban area with Mom&Pop computer shops, it might be worth a try to just walk in there and ask them to test your CPU for a sec, and then walk out with a ne CPU or Motherboard, depending onthe outcome.

hybrid2d4x4 wrote:Also try taking the board out of the case and run the test on a bench if you want to rule out the motherboard shorting (though that's probably grasping at straws).

I have shortened a motherboard once, and I think he would know if that was the case

Botanic · Post by **Botanic** » Fri Apr 17, 2009 6:23 am

Thanks for the answers!
I didn't know that the Athlons had the memory controller in the CPU...

I have three sticks of RAM in the computer. I tried them all alone in different slots. I have one stick of RAM that I could test with, which is currently in an other machine. But I doubt that there will be any difference.

The weird thing is that the errors in memtest86 comes after only a few seconds, exactly the same way every time.
It fills the screen with red "problems" and hangs after a while.

If I use the machine normally without compiling anything, I can use it for several hours, I am lucky.

If I would buy a new CPU, wouldn't I have to buy an AM2 CPU? My guess is that AM2+ is not supported by the mainboard.
For this reason I would rather buy a more new mainboard instead.
Also, around here CPUs tend to be more expensive than AM2+ mainboards.

Going to the one Mom&Pop shop that I know of around here would probably be more expensive than buying both aCPU and a mainboard online.

Buying AM3 would mean that I would have to buy new RAM. This would make it more expensive.

mgarl10024 · Post by **mgarl10024** » Fri Apr 17, 2009 8:27 am

Hi Botanic,

If it only fails under load (say Memtest or booting etc), that would suggest a heat issue to me.
You could try reseating the heatsink to check that the heat compound hasn't degraded. A bit of compound isn't expensive so this is a cheap test.

What do others think?

MG

hybrid2d4x4 · Post by **hybrid2d4x4** » Fri Apr 17, 2009 9:28 am

Botanic > I'm not sure what you mean by AM2+ CPUs. There certainly aren't any AM2+ Athlons that I know of, only the 1st gen Phenoms, which I wouldn't recommend. Even if you were insistent on getting a Phenom (or the slyly named Athlon X2 7750), I'm pretty sure those are backwards-compatible with regular AM2 boards (BIOS update may be needed), just that you won't be able to take advantage of their higher "bus" speeds.

Also, you may want to look into the thermal possibility if it hangs during the test, as suggested above.

alleycat · Post by **alleycat** » Fri Apr 17, 2009 9:42 am

So have you tested the memory sticks in another known good system? That's the only way you can be certain that they aren't the problem. Same thing with the CPU. The other item I would check is the PSU.

I had similar problems with a PC a few years ago, it would hang after a few minutes, but sometimes it would keep working for a while then hang. After staring at the motherboard for a while I noticed some of the capacitors near the CPU were bulging. I bought some new ones for about a dollar at a local electronics shop and soldered them in. It has worked perfectly since.

The same thing happened with an LCD monitor. It would switch on briefly then flicker and switch off again. I opened it up and found some bulging capacitors in the power supply section. Again, only a dollar to fix.

There's even a website devoted to this problem.

Botanic · Post by **Botanic** » Fri Apr 17, 2009 2:38 pm

The online store that I looked at has a section CPUs>Socket AM2, CPUs>Socket AM2+.
Under AM2 there are "AMD Athlon 64 X2" and "AMD Sempron Dual Core 2300+".
Under AM2+ there are "AMD Athlon X2 7750 Black Edition 2,7GHz / 3MB / 1,8GHz HT Socket AM2+ (Boxed)" and "AMD Phenom II X4 940 Black Edition 3,0GHz / 8MB / 3,6GHz HT Socket AM2+ (Boxed)".

Are these both categories interchangeable? I thought not.

I don't have a good system I coult try the sticks of RAM in.

I am quite sure that it is not a heat issue.
I am running "sensors", and can keep an eye on the CPU, case and NB temperature. They are all below 40C all the time.

I have had "bad caps" on a few mainboards before. I have also seen it several times before (I used to work as a technichian repairing computers many years ago).
This is not bad caps.

I don't think it is an PSU issue since the system fails the exact same way every time I rum memtest. Always during the same test, after the same amount of time.

My theory is that there is some kind of calculation/instruction that the CPU does that goes bad. Either when it writes/reads to the RAM, or during the calculations.

stromgald · Post by **stromgald** » Fri Apr 17, 2009 3:23 pm

I would think that it's not a thermal or PSU issue. Neither of those will cut off at the exact same percentage of Memtest. There will always be some variation depending on temperature and ramp-up of power draw. I'm betting it's a bad memory controller or motherboard. When it tries to access a certain part of the RAM for the test or perform something with that bit of memory, things go bad.

I had this issue once and replaced the motherboard, but like one of the earlier posts mentioned, it's a little more complicated with AMD and the newest Intel chips. The one I had the issue with was an early Intel P4 board.

The backwards compatibility is a little tricky. Basically, if the BIOS is up to date, AM2 and AM2+ are interchangeable. However you will lose some AM2+ features when you mix the two (it's like using fast RAM on a motherboard that doesn't support it). In addition AM3 processors can be used in AM2+ (and possibly AM2) motherboards as long as the BIOS is up to date. However you can't put AM2+ processors in AM3 motherboards.

Since your computer is having trouble, I'm assuming you don't want to try to flash your BIOS. Then, your cheapest and easiest fix would be first to buy a new AM2+ motherboard and try your old AM2 processor in it. If that doesn't work, then buy a new AM2+ processor.

Mats · Post by **Mats** » Fri Apr 17, 2009 6:12 pm

xafier wrote:As far as I am aware your AM2 socket CPU will work in an AM2+ motherboard and also in an AM3 motherboard which is set for DDR2 RAM (I am ready to be corrected though)

There's a big problem here, even the manufacturers don't seem to get it.
Asus is the worst, just check out their "AM3" boards, 15 models and only two of them uses DDR3. What a joke!!!

A true AM3 motherboard can only use DDR3 RAM and AM3 CPU's, no matter what Asus or anyone else says.

An AM2+ motherboard can use AM3 CPU's, but that doesn't make it an AM3 board. Besides that it works perfectly with AM2 and AM2+ CPU's.

Botanic: Do you have some other PSU to test with? Raising Vcore or Vdimm just a tiny bit in BIOS can make the system more stable, and by doing that you can figure out if it's the CPU or the RAM that there's something wrong with.

ntavlas · Post by **ntavlas** » Sat Apr 18, 2009 4:13 am

I would definitely try testing with the ram from that other machine. I would also try to play with ram timings and voltages as sometimes the default settings can be unstable. I know that it seems unlikely that ram timings are the issue but you never know. Sometimes problems like this can appear, apparently out of nowhere, triggered by minor changes in configuration or by using a specific application.

hybrid2d4x4 · Post by **hybrid2d4x4** » Sat Apr 18, 2009 10:46 am

Botanic wrote:The online store that I looked at has a section CPUs>Socket AM2, CPUs>Socket AM2+.
Under AM2 there are "AMD Athlon 64 X2" and "AMD Sempron Dual Core 2300+".
Under AM2+ there are "AMD Athlon X2 7750 Black Edition 2,7GHz / 3MB / 1,8GHz HT Socket AM2+ (Boxed)" and "AMD Phenom II X4 940 Black Edition 3,0GHz / 8MB / 3,6GHz HT Socket AM2+ (Boxed)".

Are these both categories interchangeable? I thought not.

They are if you're asking if they will both work in an AM2 motherboard that has an updated BIOS (assuming the board mfg released an update). My point was that the "AM2+" CPUs aren't really worth looking at. Either get yourself an "AM2" Athlon 64 X2 since you say you are ok with current speed and enjoy a small speed boost, or fast forward all the way to the AM3 Phenom II CPUs which should (according to AMD) work in the AM2 board (albeit at HT of 2.0GHz instead of 3.6). Don't bother with 65nm Phenoms including the "Athlon 7750" or the AM2+ Phenom II (which is exactly the same as the AM3 ones, minus the forward-compatibility with AM3 boards). My advice was simply to get an Athlon, not 1st gen Phenom if you do replace the CPU.