PSU question about pc

[hardbg123]

Hello,
Today i was going to build a pc out of old parts, so i bumped into trouble.
For the hearth of the pc i am going to take a lenovo pc with xeon e5420 (on lga 775 (with sticker)) but i had to select a gpu that fits into the psu wattage... I am not sure what the psu is but it says the following: The total power should not exceed 280W... I used a psu calculator and my total wattage was 260W with hd 5750 gpu. My question is the following: Will that PSU hold or i have to change it? I know it says that it should not exceed 280W but most of the PSUs are 80% efficient so will that work?
P.S. I know its an old platform, im build a very budget pc for a friend.
link: http://www.ctsestore.com/ibm-lenovo-thinkcentre-m57-280w-power-supply-liteon-ps-5281-7vr-41a9686-41a9684-9160-tower

 

[Isokolon]

that's pushing the PSU, that's never good
it depends on the quality of the PSU to determine if the PSU can actually handle it
lower quality PSU might handle 280W overall, doesn't mean they deliver even 260W on a 12V rail

however I strongly advise on getting a better PSU as constantly stressing a PSU that much won't do it much good and power spikes could make the whole system run very unstable
if it's a low quality PSU the whole setup is actually dangerous and could possibly damage certain parts of the setup

 

[madmatt30]

The old Xeon is 80w, a 5750 is 90w max.
60w for board overheads ,drives etc & fully maxed out (which will never happen realistically) that won't touch 230w.

& I'm overestimating everything vastly here.

If that PSU wattage is real you shouldn't have any issues at all.

 

[hardbg123]

that's pushing the PSU, that's never good
it depends on the quality of the PSU to determine if the PSU can actually handle it
lower quality PSU might handle 280W overall, doesn't mean they deliver even 260W on a 12V rail

however I strongly advise on getting a better PSU as constantly stressing a PSU that much won't do it much good and power spikes could make the whole system run very unstable
if it's a low quality PSU the whole setup is actually dangerous and could possibly damage certain parts of the setup

i added a link if you can check it.

 

[hardbg123]

The old Xeon is 80w, a 5750 is 90w max.
60w for board overheads ,drives etc & fully maxed out (which will never happen realistically) that won't touch 230w.

& I'm overestimating everything vastly here.

If that PSU wattage is real you shouldn't have any issues at all.

can you check the link as well?

 

[madmatt30]

To add , if you can find a 7750 cheap its a better choice , a lot more powerful than the 5750 , bus powered & has a 40-50w power draw.

 

[madmatt30]

That PSU will manage it.
However as I said the 7750 is a better choice , to run the 5750 you'll be using moles to PCI adapter , with the 7750 you won't need to.

 

[Isokolon]

total power shouldn't exeed 250W according to the link you provided
also if I'm reading this correctly it can only output 220W on the 12V rail
depending on age and build quality this could be a problem but doesn't have to be
unfortunately I gotta go and can't search for a good review on that unit...