250w or 300w psu?

[jeffreyzhou3]

Hi I need help deciding for a psu for my computer I’m building

Motherboard
https://www.discountelectronics.com/dell-optiplex-780-motherboard-usff-g785m/?gclid=CjwKCAjwuO3cBRAyEiwAzOxKslz-e2o981rC9ksXbFc6NA95j5UPUoU2MxxENxwG32UTfMCduiDNbhoCdxwQAvD_BwE

CPU
Intel core 2 quad 6600

Ram 4 gb (2 sticks)

Gpu
Undecided but will get like 2gb card

Should I get 250 or 300 watt psu

 

[volkgren]

Knowing the max wattage of a PSU is not knowing very much. What are the exact models of the PSUs?

 

[jeffreyzhou3]

Sorry I forgot
Here’s links

https://m.ebay.com/itm/Dell-Optiplex-580-760-780-960-DT-Desktop-L255P-WU123-FR597-RM110-Power-Supply/272585291621?hash=item3f77597765:g:9bkAAOSwPc9WvMKz


https://m.ebay.com/itm/Dell-OEM-305W-Power-Supply-for-Optiplex-Mini-Tower-380-780-960-990/153039632842?hash=item23a1df79ca:g:d7wAAOSwAnhbC6Hm

Also how much wattage does CPU use?

 

[Marlin Schwanke]

That’s some pretty old gear. Do you have a BTX case for that BTX mainboard? Anyway you specified a Dell Optiplex 780 mainboard. The Dell Optiplex 780 power supplies were typically 255 watt. There were some 280 and 235 watt as well. I’d say leave yourself a little headroom and go with the Dell 280 rather than the 255 you are looking at.