Replacing bad caps on motherboard

[Computerhulp Looman]

Hello,

i have an asrock x58 extreme motherboard. Problem is, when i benchmark graphics, it reboots randomly. Now i found some capacitors on the mainboard which look dirty and i want to try to replace them. They're close to the first x16 pci express slot.
Question is, whether i just can take a capacitor with same uF, high temperature withstand and replace them? Or, does the ripple current also apply and do i have to take notice of that.

Added a photo of the capacitors.

Grtz

 

[GhislainG]

They should be replaced by capacitors having the same specs. You tried a different GPU and PSU and it still reboots?

 

[Computerhulp Looman]

Different gpu, yes an gt 710, it only takes about 30 watts, so it doesn't really take full power. It doesn't reboot, but it's so slow. But thing is, if i use this radeon 5970 in another pc with amd board, it works, benchmarks without problems. Same specs: these are i believe Nichicons caps: LF 100C 5K 9X2 and LF560J 5K 9X2. They are 10uF and 56uF. Probably the replacements are Panasonic 25SEP10M and 20SEP56M.
The caps are a bit coloured, so are not clean anymore. Read somewhere on the internet that that means they're bad caps. And they are right next to the pci express slot i use for the radeon gpu. The psu is like only 2 or 3 years old, but the mainboard shows at 3.3 volts only 3.0 volt(could also be due to bad caps). Don't have another psu with 8 pin mainboard connection, so can't test that it's the psu.
Yes, i lend the radeon out to someone, he also had reboots. It doesn't really make sense, one thing says it's the mainboard, another it's the radeon.

 

[CountMike]

Those solid state caps as opposed to electrolytic ones are difficult to troubleshoot by looks only, only very high overheating may discolor them.

 

[Computerhulp Looman]

would be handy to have the code scheme they used at nichicons back in 2009 to letter their caps.

This is the way they letter their caps now:

Image

 

[GhislainG]

If the Radeon 5970 caused the same reboot issue in another PC, then look no further.

 

[Computerhulp Looman]

Did another test with the radeon in an amd pc. No reboots there. 4k furmark with 29 fps avg.

 

[Computerhulp Looman]

Those solid state caps as opposed to electrolytic ones are difficult to troubleshoot by looks only, only very high overheating may discolor them.

Hey Mike, the board is 8 years old, might have gotten some users damage. The only card that gets real hot it the radeon 5970. The complete house of the card gets hot too. Then the caps are right beneath the card, so might have taken some heat too.

 

[Computerhulp Looman]

Here the specs of the lf series: Image.

LF 100C 5K 9X2 =cap1
100: 100 uF
C: 16 volt

and
LF560J 5K 9X2 =cap2
560: 560uF
J: 6.3 volt

Now i've found two cap's matching for the most specs. Just ESR for one should be 24mOhm and the cap i looked at at the shop was 12 mOhm and the leakcurrent of the new cap is way lower.

 

[Computerhulp Looman]

Fixed it with thisi: Image

Must add, overclocking your cpu with the radeon 5970 doesn't make it very stable. But non overclocked cpu, it's very impressing to see the 2 gpu's working at full capacity.

 

[Computerhulp Looman]

Update: it's been running good for almost a day and this morning it was soup again. Right now, it's running quite stable with only one core. That makes it a 5870 or 5850 gpu.An Mstech 850 watt psu, according to the internet it's a bad psu with 350/400 real watts. Then this seems quite logic to me. The psu can barely handle the gpu and i should get a better one.

*edit: reducing gpu clock frequency from 750mhz to 610 mhz seems to help for now running it in crossfire mode. The voltages the motherboard reads from the psu are somewhat low:3,3 volt=3.05volt, 12 volt = 11.6 volt on the mainboard. Checked the caps of the psu, but they seem all right, no bulges or leaks.

 

[Computerhulp Looman]

Now this morning it was soup again. What i tried this time, was monitoring the voltages during a benchmark. Now the 12 volt drops considerably and might be the cause of the reboots. Image

 

[GhislainG]

Same issue with the 3.3V rail. Using a DVM would be more accurate than software.

 

[Computerhulp Looman]

Same issue with the 3.3V rail. Using a DVM would be more accurate than software.

Hey Ghislain,

been testing the psu on another mainboard( much lighter one, dual core, 4 pin motherboardpowerconnection) and there the voltages in the bios seem all right. After reading some of my psu mstech 850 watt on the internet, it seems some say it's 400 real watts. Trying another psu, a zalman 400 watt with molex to 8 pin EPS socket converter.

 

[Computerhulp Looman]

This is the hwmonitor screen after a successfull run of 720p in furmark: Image

My psu has 2 +12v rails, and only one of them dropped a lot. Reconnected the powercables.

This is the hwmonitor after a successfull run of 1080p in furmark: Image

 

[GhislainG]

The voltage on the +12V rails should stay within the specs: +11.4 to +12.6 volts.

 

[Computerhulp Looman]

The voltage on the +12V rails should stay within the specs: +11.4 to +12.6 volts.

It's closer to 11 volt. But still running. Used a converter from molex to pci express power( 6 pins) and the regular pci express power (8pins) from the psu.
I do have lying around a Zalman 400 watt psu. It is quite stable running an amd quad core@4ghz, 3gb ddr3 memory and the radeon 5970.
Could try that psu on my machine: xeon cpu, radeon 5970, 8gb ddr3 memory.

 

[GhislainG]

You lose nothing trying it, but check the 12V rail(s) output. 400W is meaningless if it's an old P4 PSU.

 

[Computerhulp Looman]

You lose nothing trying it, but check the 12V rail(s) output. 400W is meaningless if it's an old P4 PSU.

Jow, replaced the psu with the 400 watt zalman. Ran half furmark's 720p benchmark and these are the results: Image.

The low 3.3 volt is solved by replacing the psu. The 12 volt is still low, like 11.1 volt.

 

[Computerhulp Looman]

Same issue with the 3.3V rail. Using a DVM would be more accurate than software.

Then probably your usb ( front and back) is also not working as it should. With the zalman psu and 3,3 volt, the back/mainboard usb connection works better than with the 3.1 v psu.

 

[GhislainG]

Could you borrow a known good and powerful enough PSU to test? You can obviously replace the caps, but I'm not yet convinced that would resolve all issues.

 

[Computerhulp Looman]

Could you borrow a known good and powerful enough PSU to test? You can obviously replace the caps, but I'm not yet convinced that would resolve all issues.

Hey, i took the mstech 850 psu, and put it in the amd mainboard and it gives me right voltages, even with the ati 5970 inserted. So it isn't a psu problem, but a mainboard.

Thought, maybe it's that simple to make photo's of the caps on a mainboard( discolouring is more easy visible) and replace all the caps that show discolour.

One thing, on the x58 mainboard the 3,3 volt with the mstech psu is not good, with the zalman it is 3,3 volt. But if only used 4 pins to the mainboard (amd mainboard) it shows 3,3 volt.

 

[GhislainG]

Ultimately it's your decision. Mine would be to either replace the motherboard or sell the good parts and build a new and faster system.

 

[Computerhulp Looman]

Ultimately it's your decision. Mine would be to either replace the motherboard or sell the good parts and build a new and faster system.

Still thinking of replacing the caps. The brown visible on top op the caps, it's leaked from the inside of the cap. That and it's like 8 years old mainboard. Don't think it's cheap to get another mainboard with cpu, but i could buy the same socket mainboard as new instead. The overclocked xeon cpu, it's very fast when all cores are active. Like a much newer i7 cpu.
Had some trouble with the booting of the computer, but after cleaning the ram slots, it boots right.
Btw i found another 6.3 volt cap which is brown, all near the pci express slot though. A bit strange, that the other psu gives better 3,3 volt readings and the same 11.1 volt. And that last sateruday, the complete day, the mstech psu and the xeon and radeon 5970 were working right and at full speed. While the day after it didn't work. Only thing i did was clean the mainboard with an air compressor.

 

[GhislainG]

You can definitely replace the caps; it won't be expensive and it may resolve the issues.