cetkat

Compaq Presario S4020WM
OS: Windows XP SP3
Proc: 2.00 gigahertz AMD Athlon XP
RAM: 2 x 512MB
GFX Card: S3 Graphics ProSavageDDR
MB (Belarc Info): KM266-8235
Serial Number: 137928-32122130
Bus Clock: 133 megahertz
BIOS: Phoenix Technologies, LTD AM37320 08/01/2003

I came across justpassingby's post in another thread (quoted below). I had to replace a memory stick a couple days ago due to a failure I discovered while updating to SP3. I ran PC Doctor (DOS version) provided by HP for my system, and the only hardware error it came up with was for that one memory stick. It seems to have one Temp test, but nothing for voltage. I have answered the power supply questions mentioned and would like to know if there could be a problem. If there isn't, could it be due to changes in the power going INTO the power supply?

Power Supply Sticker Info::
Brand: Bestec
Model: ATX-250-12Z REV.:D
Wattage: Below
Amp on 12V: Below

OUTPUT
250W Max

+12V / 14A
-12V / 0.8A
+5V / 25A
-5vSB / 2A peak 2.5A
+3.3V / 18A

+5V & +3.3V / 165W Max
+5V & +12V / 218W Max


I don't believe my BIOS lists that information and I want to avoid restarting at the moment since I'm trying to solve another problem. So, I downloaded a monitoring program. I included the +12V changes. All other voltage values have remained constant over the past couple hours save +5V which has been 4.78-4.81.

ThorXP

For checking the memory I would not use a DOS type program but here is Memtest please downlaod and run it for a few hours.

Go here and download the Memtest Release and run it
http://www.memtest86.com/

Tutorial: How to use Memtest
http://www.techspot.com/vb/topic62524.html

dai

see if you can borrow a 450w power supply to try in it

cetkat

I ran the Memtest program. It didn't turn up any errors. Of course the faulty memory stick has already been replaced, so that's good.

I mentioned the PC Doctor because of the CPU & Board tests, but I actually used a stand-alone memory test called WinDiag to check the RAM. The newer stick in my system checked out fine, but the older one I replaced failed every test. It also would not boot windows when it tried to load with just the failed stick.

Dai: What would I be able to learn with the 450w? Do the results I posted show a problem? There is a power supply on a system that's not being used for now (not mine) but it's homemade and I can't find any identification on the supply itself. Other than that I'd have to buy one.

dai

try it and see

cetkat

See what exactly? What am I trying to change?

dai

your trying to check if the psu is the probem

cetkat

I get that part. Let me see if I can explain my question a bit more clearly..

I'm trying to find out if the psu caused the memory failure. So since the failure can't be undone or repeated for testing, I look at the psu's performance - if it's faulty, that means it could have created the problem & I need to get a new one. So how does putting another one in temporarily determine this? Am I looking for some improvement in temp/fan/voltage?

dai

agp requires 18amps on the 12v+ line you don't have 18amps on the 12v+ line

cetkat

So, it would have to be upgraded in order to use the slot.. good to know. However, my graphics card is integrated. Does anything else need 18amps?

cetkat

Dai, I don't have alot of cash.. but if it's necessary I'll go ahead and purchase a 450W or better. Do you still recommend it?

ThorXP

Before purchasing a new power supply I do have a question since you have an HP and installed service pack 3, are you running media center as the OS?

cetkat

No, it's a normal XP Home install..

ThorXP

I know HP has a problem with service pack 3 but as far as I know it is only with the media center edition. You might want to go to HP web site and check and see if you can find anything there about your problem, I believe they have free email tech support and from what i have heard they are really good and quick.

cetkat

Yeah, my SP3 is fine. The memory went before the upgrade.. It was actually a message about a corrupt SP3 installation file that clued me onto the problem. Why it says that instead of RAM corruption is anyone's guess. The RAM had only partially failed, and I was able to replace it with a stick from another machine.. so I'm happy. This is more preventative care than anything. I don't want anything else to break, but from the look of it everything is functioning ok. I'll take a look and see if HP has anything about known issues with my supply.

justpassingby

If speedfan reads the voltages correctly your +5V line is nearly out of specs. Replacing the power supply might help. According to ATX specs the voltages have to stay in a +/-5% range of their nominal value, the closer the better. Your 5V is too close from the 4.75V limit to be healthy. Problem is that you can't be sure that speedfan (or any other software) gives you the correct readings if you can't double-check them in the BIOS. The BIOS being build around the motherboard will give fairly accurate readings, but any software trying to read those voltages within Windows would need to know the exact sensor layout of your motherboard. Low end motherboards sometimes lack the proper sensors, causing misreadings.

To add to what you quoted in your first post, the ram can also be damaged by power surges from the wall outlet if the electrical tension is bad at your place. Power surges or subvoltages would eventually damage the power supply or other components (motherboard, video, hard drives, ...) but the RAM will often be the first part to go. I had that problem at my place, I returned 4 memory sticks before finding out that my wall socket was giving out unstable 236V instead of 230V (european voltages). No wonder my light bulbs don't last more than 2 months. I bought an UPS and I can hear it switch on the internal battery once or twice a day because of power surges.

If you have a multimeter you can check the voltage and tension you get from the wall outlet. You can also check your power supplies lines directly if the voltages are not reported in the BIOS : Test your power supply with a multimeter (may not work if your PSU is proprietary).

Your rig is low end but a 250W power supply won't take you very far. Capacitor aging also means it looses efficiency over time. How long have you had this computer and power supply ?

Windiag is ok to test the memory, but you could give memtest a try since it'll run different tests. You should leave the tests running overnight to make sure there are no problems at all.

Also check that the ram stick you used to replace the failing one is the exact same model as the one you kept. Different brands and models will use different timings. Timings will be automatically adjusted for the slowest ram stick but if the other stick can't work properly at those timings it'll cause stability issues.

cetkat

Thanks for your reply! Just checked the BIOS. I was right.. all it lists is the CPU fan speed and temp (both of which equal speedfan's readings however).

The last couple places I've lived at have had unsteady power. I never tested the lines, but I heard it fluctuate. It sounds like it fits the problem then. It's the older RAM that went, and now there could be a PSU issue. I have a surge protector, but that can't supply power.. obviously.

I do remember having something that reads low voltage. I'll have to see if it would work. If it is proprietary, does the pinout arrangement negate being able to test, or would I just have to figure out which connection is which?

About 5 years, I think. But I got it as a newer refurb from a shop.. so maybe 7 max considering speed if it's the original supply.

I ran memtest for about 3 hrs. I'll run it for longer.

I never knew it mattered much, so I've actually always had mis-matched memory. Right now I have MemoryPower(old) and Kingston(new) PC3200. The stick that failed was Viking PC2100.

justpassingby

Low end or cheap motherboards often lack the voltage sensors part in their BIOS, sometimes you won't even get the cpu temp and fan speeds. The voltages sensors are not the same as the temps and fans sensors so this doesn't prove that speedfan's readings are right.

Just grab a known good 300W+ power supply to test your computer with and see what voltages speedfan reports. If the 5V line now reads between 4.9 and 5.1V then there's a good chance that speedfan's readings are ok and that your old 250W PSU is reaching the end of its life.

Edit : I think compaq presario desktops use regular ATX PSU's but better wait for dai or someone else from the hardware team to confirm this.

I think a surge protector will only prevent that a big surge damages your system by cutting the power before the surge gets to your computer. It won't prevent small voltage fluctuations to wear down your components. If you have bad tension at your place you need an UPS (uninterruptible power supply) that will regulate the current before it gets to your computer. It's only needed for sensible electronic devices like computers, bigger or less sensible devices should accommodate with small spikes. If the current isn't too bad a better power supply would already help.

Wait for dai or someone more knowledgeable than me about electronics to answer that part, but it's probably a regular ATX supply.

I'd replace a 5 years old power supply at the first signs of weakness. The efficiency loss depends on the quality of the power supply but it can be as much as 30%.

Download and install cpu-z. Each stick stores default timings in its SPD. The memory tab in cpu-z will tell you the timings that are used currently and the SPD tab will give you the default timings for each memory stick. You could also check MemoryPower and Kingston's websites with the part number you'll get from cpu-z or on the sticks themselves. The sticks being the same size and frequency helps but even if they use the same timings it's always better to use a matching pair.

edit : since this is all about memory and psu I'll move you to the power supply section.

dai

this is on special
http://www.newegg.com/Product/Produc...82E16817371006

cetkat

I just finished running the Memtest again. I let it go for 18 hrs this time and didn't turn up any errors.

Are you saying that a better PSU can deal with spikes more efficiently? Or just that the more stable the PSU the better, and I'm right to wish for a UPS?

Well, I decided it would be easier and more accurate to test with a multimeter, so I did that. I did figure out that you can test proprietary PSUs too btw (it's just a different wire/color order on the connector), however it does look like I have a regular ATX (my mobo actually has the wire types written on it). The multimeter was a high-end model so I had to test on the 200 setting rather than 20, but it reads a 1.5V battery accurately. I tested my 20-Pin connector & first Molex to get my readings. I did the Molex at first (since the 20-Pin wouldn't read due to it being hard to connect to through the back), but then I realized that a ground was a ground & used the Molex to help do the 20-Pin tests. I also ran Prime95 during the 20-Pin test since it was suggested elsewhere and made sense. Here's what I got on the lines:

+12V : (20-Pin) 12.1-12.2 ; (Molex) 12.0-12.1
+5V : (all) 4.9
+3.3V : (all) 3.3

So, is the 4.9 good enough for this specific a test, or would I be better off with a higher number (ie a new PSU)?

Thanks for that deal! So my PSU should be ATX then? It seems like it is, but I did find that the 5.5v Pin 20 on this diagram doesn't quite match up to mine. It still reads the same voltage, but mine has two wires sticking into it.. red and pink. Is that normal?

That's really helpful, thanks! I ran the program, and luckily my timings are exactly alike.