Have a dell 8400 trying to replace the psu.best buy sold me a 400watt. my old one is a 350 and it is a 24 pin the new one is a 20 pin with a 4 pin beside it how would i hook this up? also the old plugs are marked with numbers on them the new one dont. how do u no what goes where?

welcome to the www, where answers are www told
parts not sold buy the oem, are sold used on the web.
using 3 ways.
1:ebay
2: amazon
3; or google planet earth for it.
there is no other way
there are 3 cures here.
1: find the rare board on earth.
2: upgrade it to better newer board. that is supported, asus is best.
3: fix your gee no symptoms told, and the coin cell is dead.4:
4: buy a newer PC not this junk. or DYI PC ASK !


your relic is too old to expend real cash on it ever.
2001 TECHNOLOGY, 21 YEARS OLD.
Intel Pentium 4 CPU
Socket 478
533MHz
Chipset
Intel 845GV ( ding ding ding relic, bell rings)
Intel ICH4
omg no SATA PORTS , NO PCI EXPRESS SLOTS .
DEAD FOR NOT USEING 4 PIN AND 20 PSU CABLE TO PSU
OOPS.BOTH POWER CABLES TO MOBO MUST BE GOOD.
NO W7 AND UP SUPPORT , INTEL.COM SAID SO.

BUY OR BUILD A PC WITH I3 , INTEL CHIPSET UP.
CHIP SET H55 UP 2010 UP. I7 ,4 CORE YES.

Thanks for the information, pretty detailed, I recommend you get all the specs of the Dell dimension 8400 motherboard and buy a compatible one, of course check the CPU first at a friend's home and if the CPU is fine, go ahead and buy and install a new one.

Most of the 24 pin PSU Have the +4 pins colored in green. The green part can be removed by un-engaging two clamps.

Test your PSU or replace it if your power supply units fan is not working your PSU is faulty

One bad lead can cause a computer to continue on a cycle or to shutdown or fail to detect or boot up your hard drive

Test all leads that attach from the ((motherboard to your hard drive)) including electrical extensions,IDE,SATA

the leads from your motherboard to your hard drive make sure they have a secure connection and are not faulty or just replace them there probably old and faulty

make sure all leads that are attached to your drives dvd\cd 3 1/2 inch floppy have secure connections and are not faulty or just replace them they are probably old and faulty ?
dont forget to vote
hope this helps

You should be able to find stuff for that dell on ebay good luck Jonny

yes you can try checking the processor

Be sure that the ATX or BTX power cable (the rectangular cable with 20 or 24 pins) is securely fit into the motherboard. Re-seat it if needed. Also, check the +12V 4-pin adapter (if exists) is seated, just like the 20/24 pin is. If that doesn't solve the problem, be sure that the PSU is switched on and is at 120V (USA) before plugging in the power cable. If that doesn't work, contact the computer manufacturer or the PSU manufacturer (depdending on what you purchased.)

Hope this help!
Robert W.

please check whether there is burning in the motherboard due to this there is no switching in the motherboard. plz get the motherboard repaired. their is no problem in replacing the 20-pin psu

the reason for the melting could be down to one or the other, i would deffinately change the motherboard as it may be the reason for the melting and just keep an eye on the PSU