Asus boards got old n leakeage transistors

[Calchaqui]

Hi, I got several old p2b-f, cusl2-c, tusl2-c. They were in storage for many years and all of them start having "Power on and Power off" the TUSL2-C when turn on, fans spin for 2 second and then goes into sleep mode, sometimes it post OK, the p2b-f when plug-in in to the AC line fans spins for 2 sec without power it on, cusl2-c turn-on byu itself and never turn-off (dont respond to power-off) . It think, u guys are wiser than me, gotta be some kinda leakeage in the pw-sw line, i cant identify which transistor is, or if a small cap maybe smd cap is shorted or something else :S, but the problem in all my mobos is related with getting old in storage.
http://en.wikipedia.org/wiki/Leakage_%28electronics%29


Thank you from Argentina

[RJARRRPCGP]

Re: Asus boards got old n leakeage transistors

My Asus P2B-F uses nothing other than real good caps. The BIOS got flashed with the latest BIOS version and has a Coppermine 850 in it right now.

And I never had problems with cold booting it.

[pfrcom]

Re: Asus boards got old n leakeage transistors

I don't have problems with my CUSL2 with P3-1000 or TUSL2-C with P3-1400S

Apart from the PS2 connector in this thread badcaps.net/forum/showthread.php?t=829

Have you tried different power supplies ?

[Kiriakos GR]

Re: Asus boards got old n leakeage transistors

When I did read about the TUSL2-C it was like seeing a ghost.

Recycle them !!

I still have one TUSL2-C Bios chip as spare.. or better said as proof of my personal stupidity about paying the price premium for short lived motherboards.

[Calchaqui]

Re: Asus boards got old n leakeage transistors

I don't have problems with my CUSL2 with P3-1000 or TUSL2-C with P3-1400S

Apart from the PS2 connector in this thread badcaps.net/forum/showthread.php?t=829

Have you tried different power supplies ?

Yes I had it to, took off the C151 8-legged CAP .

Yes, all my Asus boards have good caps, but I thought that the power-on problem could be shorted little SMD caps or little transistors. MOST of more than 10 years old mobos start having problem in the CMOS battery line (with new batteries) because of a little 3v transistor near the battery,

[momaka]

Re: Asus boards got old n leakeage transistors

I have an ASUS CUR-DLS motherboard that sometimes won't boot either (I press the power button, all of the fans spin for a split second and then it turns off). If I wait a few seconds I can repeat the process. Doing this over and over will eventually boot the motherboard. And sometimes it starts first time. I haven't spend any time to look into it, but given that it's an ASUS, I'm not very hopeful.

[Calchaqui]

Re: Asus boards got old n leakeage transistors

I have an ASUS CUR-DLS motherboard that sometimes won't boot either (I press the power button, all of the fans spin for a split second and then it turns off). If I wait a few seconds I can repeat the process. Doing this over and over will eventually boot the motherboard. And sometimes it starts first time. I haven't spend any time to look into it, but given that it's an ASUS, I'm not very hopeful.

Exactly the SAME problem with a CUSL2 and TUSL2C, it has to be a transistor in the pwr switch line, but there are many...:S

[RJARRRPCGP]

Re: Asus boards got old n leakeage transistors

I have an ASUS CUR-DLS motherboard that sometimes won't boot either (I press the power button, all of the fans spin for a split second and then it turns off). If I wait a few seconds I can repeat the process.

The shutting off could be the PSU. IIRC, seems to be common with cheap PSUs.

Never had that problem, but OTOH, my MSI 845E Max randomly fails to POST on a cold boot.
Sometimes, I press the power button and all I get is fans and LEDs until I power cycle multiple times.

Especially when it's been off while attached to my air duct with arctic air. (Used for OC'ing.)

The problem may be be related to my SmartPower 2.0 500W PSU, even when I had that problem long before any of the Fuhjyyu caps started bulging, and when I did get a bulge, it was only the Fuhjyyu cap next to the outer fan, which could be the +5V standby.

My Asus P5QL Pro and Fortron PSU never had a cold boot issue.

[momaka]

Re: Asus boards got old n leakeage transistors

The shutting off could be the PSU. IIRC, seems to be common with cheap PSUs.

Negative. I tried several of my known good power supplies that I recapped myself and used for many other computers.

My CUR-DLS actually came stock in a HP Netserver E800, and the PSU in that was a 200W Astec. It's anything but cheap.

Exactly the SAME problem with a CUSL2 and TUSL2C, it has to be a transistor in the pwr switch line, but there are many...

I wonder what ASUS messed up on then.

[RJARRRPCGP]

Re: Asus boards got old n leakeage transistors

Negative. I tried several of my known good power supplies that I recapped myself and used for many other computers.

My CUR-DLS actually came stock in a HP Netserver E800, and the PSU in that was a 200W Astec. It's anything but cheap.


I wonder what ASUS messed up on then.

Looks like you may have dried up caps.

[momaka]

Re: Asus boards got old n leakeage transistors

Nope.avi
All are high quality Rubycon/Sanyo electrolytics with some Fujitsu RE series polymers around the CPU.

[Calchaqui]

Re: Asus boards got old n leakeage transistors

Nope.avi
All are high quality Rubycon/Sanyo electrolytics with some Fujitsu RE series polymers around the CPU.

I think those are the nasty leaking little ones

[momaka]

Re: Asus boards got old n leakeage transistors

I'll try to have a look at my board this weekend (don't have it where I am right now). I never seen these die on motherboards, so I doubt that may be the problem, but we will see.

[Calchaqui]

Re: Asus boards got old n leakeage transistors

I'll try to have a look at my board this weekend (don't have it where I am right now). I never seen these die on motherboards, so I doubt that may be the problem, but we will see.

I'll be waiting for your feedback fella

[Calchaqui]

Re: Asus boards got old n leakeage transistors

I've found out why the Asus had power up problems (power up by itself, or do not power dont never) I thought that was a BIOS-CMOS-BATTERY circuit problem, but the one big transistor getting shorted is 10N03L in the VIO VRM the other one is a little affected too. Do you recommend me using my HeatGun http://cfnewsads.thomasnet.com/image...493/493185.jpg or what?, I already have the replacement fet.

[c_hegge]

Re: Asus boards got old n leakeage transistors

given that it's an ASUS, I'm not very hopeful.

ASUS boards were practically bulletproof back in those days. Even their early Socker 478 boards were often OK (when they didn't use bad caps).

[Calchaqui]

Re: Asus boards got old n leakeage transistors

ASUS boards were practically bulletproof back in those days. Even their early Socker 478 boards were often OK (when they didn't use bad caps).

Right, in the 440LX era Asus used lota IQ caps. Aopen and Intel were the others with high quality caps

[c_hegge]

Re: Asus boards got old n leakeage transistors

^
Yeah, but at least they usually were fine after a recap. These days, ASUS, don't get bad caps. They just die for no obvious reason.

[Uranium-235]

Re: Asus boards got old n leakeage transistors

^
Yeah, but at least they usually were fine after a recap. These days, ASUS, don't get bad caps. They just die for no obvious reason.

more or less a misnomer, that was true just a few years ago cause asus started to use tons of nvidia chipset boards, and those died for pretty much the nvidia chipset reason. NOW, I have yet to get an asus board within the past 2 years that died on me or any of my customers. Though I still prefer gigabyte or MSI

[ChaosLegionnaire]

Re: Asus boards got old n leakeage transistors

sry to hijack this thread *a bit* but what about asrock? since its a subsidiary of asus, it shud be as good right? asrock got those premium gold polymer caps thing on some of their boards. example. but they fail to specify exactly what brand and model of caps they use. hope its good too...