Help identify a tantalum capacitor - Page 1
Forum section: electronics / repair

author: Mikey5791
author_rank: Contributor
timestamp: May 19, 2020, 01:23:10 am
content: Hi,Greetings to all. I am newly registered and hope to find some kind advice here.Fyi, i am repairing an overheated Acer Aspire 4738 laptop which causes os to hang. Had changed a new cpu fan and thermal paste but it still hang after about 5 minutes running.So i am proceeding to check on the back portion of the cpu and noticed three smd tantalum capacitor. It has marking of 330 on first row and 08D1Y. Sorry i am unable to get any schematic or parts list from google. Can these be 330uF caps? But what voltage are those...2.5v or 6.3v orI had checked esr is about 17Ω which i think is a bit high. No wonder the cpu is super hot.Thanking in advance for anyone who can give advice and help where necessary.

author: Whales
author_rank: Super Contributor
timestamp: May 19, 2020, 03:18:43 am
content: I would recommend less invasive tests before going as far as removing caps. Memtest would be a good start. Any reason you think the caps are bad, or are you stabbing in the dark?Easiest way to find the voltage rating is to measure the voltage across them whilst the computer is running and work from there. Ones directly under a CPU are likely to be extremely low voltage (ie 1.5V and below), other chips will vary.

author: aqibi2000
author_rank: Regular Contributor
timestamp: May 19, 2020, 10:41:13 am
content: Really common issueThey are 330uF capacitors, if you search Toshiba laptops you’ll see the same caps problem

author: fzabkar
author_rank: Super Contributor
timestamp: May 20, 2020, 09:12:44 am
content: Service manuals, circuit diagrams:https://elektrotanya.com/?q=showresult&kategoria=All&kat2=All&what=Aspire%204738330uF, 2V, 7343 Tantalum Capacitors - Polymer SMD:https://au.mouser.com/Passive-Components/Capacitors/Tantalum-Capacitors/Tantalum-Capacitors-Polymer-SMD/_/N-75hr2?P=1z0wrktZ1yzkwxh

author: m3vuv
author_rank: Super Contributor
timestamp: May 20, 2020, 10:50:10 am
content: Ive a dell insiron that started doing the same,said cpu temp to high and shut down,normaly in under 60 seconds,i replaced the heatsink + fan from a spare machine,still the same,a few months before this i replaced the cpu with a 2.5 ghz from a 1.6 model,long story short the cpu was faulty,replaced it and bingo

author: Mikey5791
author_rank: Contributor
timestamp: May 21, 2020, 05:02:42 am
content: Hi,Done the memtest much earlier and it passed and i also swap the memory card to use on another laptop. The memory is good.I will go ahead with ordering and replacing allthe 330uF caps and see if the os freeze. The online order might take up to a month during this lockdown period. If it still the same, i will try replacing the cpu. If all is well, i will report back the good news.My sincere thanks to all of you who help contributing many solutions in a clear way.Much appreciated.

author: Mikey5791
author_rank: Contributor
timestamp: June 07, 2020, 04:10:09 am
content: Hi,Received the 330 caps yesterday and replaced all the old caps with new ones.The system boots to bios and Windows 7 for less than a minute, then the screen blacks out.Power led and fan still running.Shuts down power and restart. Now the os doesn't boot. Just black screen.

author: james_s
author_rank: Super Contributor
timestamp: June 07, 2020, 04:17:12 am
content: Is the CPU a soldered BGA? If so then I'd expect bad soldering, it's a very common problem with laptops, the Xbox 360 was notorious for it too.