ASRock Dual Sata II repair help needed

[sgt_az]

I built eight computers in 2006 with ASRock Dual Sata II motherboards that have run flawlessly until now. I've had two motherboards die in the past month with the same condition. When I try to power them up the CPU fan comes on but nothing else, no hard drives, no floppy or CD drives, no video, no post attempt. I've replaced caps in hundreds of Dell and Asus motherboards over the years and these two boards' caps appear to be ok.
I have a Bob Parker Blue ESR meter that I've spot checked a number of the capacitors with. Does anyone have any experience with this particular motherboard? I've already used the one spare I had in stock and so far haven't determined what is causing this failure. I've looked for used boards online as well but really don't want to buy the same board if I can't repair them in the future. Thanks.

[momaka]

Re: ASRock Dual Sata II repair help needed

I don't have much experience with this board yet other than I just got a computer with the same board (AsRock 939Dual-SATA2) about 2 weeks ago from the trash. It works okay so far, but I noticed that the board area under the RAM MOSFETs has started to turn dark. Looks like AsRock (or ASUS rather) has cut some serious corners there. Even with a single stick of RAM in my board, the RAM MOSFETs still run burning-hot.

Not sure if that's the cause of the issues with all of these boards, but IMO it's a good place to start. So check if the RAM MOSFETs are outputting the proper voltage. The RAM MOSFETs are located right under the RAM sockets. If I'm not mistaken, one of them should have 2.5V.

If that's not the issue with your board, then perhaps try a full recap. Mine is filled with Ost (except the CPU VRM high, where there are some Chemicon KZE caps) so I imagine yours is just like that as well. Will likely be very time-consuming since there are a lot of caps, but probably still worth a try.

Other than that, I don't know what to suggest. ASDS (ASUS Sudden Death Syndrome) perhaps :\ .

Before calling it dead, maybe try resetting the BIOS (pull battery) or even re-seating the CPU/RAM. Also, have you tried running the computer barebones only (i.e. just the motherboard with CPU, RAM, video card, and PSU)?

[severach]

Re: ASRock Dual Sata II repair help needed

Try a POST port 80 card.

Sounds like you are doing in circuit ESR testing. It takes a lot of experience to know whether the in circuit ESR readings are believable or not. Pull the caps to be sure, and if they are junk brands, replace them anyways.

Many cheap cap brands fail without bloating or spewing so pull and test. The caps in the hot areas are the most suspect.

[sgt_az]

Re: ASRock Dual Sata II repair help needed

I went through and pulled all of the caps up in the CPU and RAM areas. They all tested ok but I went ahead and changed them anyway. I still have the same results. CPU fan turns on, nothing else, no post, no beeps, I've ordered a port 80 card which I will test with once it arrives. Thanks.

[sgt_az]

Re: ASRock Dual Sata II repair help needed

I had already reseated the CPU. I actually tested it in another system to verify it was still good. I tried new RAM, tried to start it with just the CPU, RAM, and a video card. I pulled the battery and reset the bios as you suggested. Still no luck.

[RJARRRPCGP]

Re: ASRock Dual Sata II repair help needed

Watch out, it looks like Asrock may be using Evercon caps.

Evercon is believed to be the same company that brought us GSC!