Do I need a new motherboard?

saltscar

I have an ASUS P5KC. I recently installed a new graphics card, EVGA GTS250 and upgraded my PSU to 700 watts to cope with it. After installation my computer will not boot up. On pressing the power button all fans start and the motherboard light shows, but then it shuts down and will not go into POST. I have double checked all connections reset CMOS. I have used the PSU from another computer and it does the same. Any fuirther ideas anyone?

m5rcc

Does it go on with GFX and memory only?

CHR15

I've got a GTS250 card. It is one seriously power hungry beast.

I have a 750W PSU with (most critical) 43A combined on the 12v rails (+12v1 = 23A, +12v2 = 20A)

Have a look on the side of the PSU and see what current is available on the 12v rails

I'm not sure if all GTS250 cards are the same but mine needs TWO PCI-e connectors fitted for it to work.

I had a power splitter in the box, One side connected to the PCI-e plug from the PSU.

I needed another splitter to go from the second PCI-e socket from the GTS250 to be fed from TWO standard molex connectors


.

saltscar

My psu has 24 amps on the 12v rail. I have only one additional socket on the card that takes 12 v from the PSU. The card works fine on another computer. But I don,t know if I damaged the board when fitting the new PSU, having to take a large CPU cooler off the get the PSU in.

saltscar

m5rcc. no it does not work with graphics and memory only:mad:

Nex0

Does it work with your old graphics card?

RobTang

saltscar wrote: »

My psu has 24 amps on the 12v rail. I have only one additional socket on the card that takes 12 v from the PSU. The card works fine on another computer. But I don,t know if I damaged the board when fitting the new PSU, having to take a large CPU cooler off the get the PSU in.

Are you SURE you re-mounted the cpu cooler properly ? even if one of ths mounts ins't on properly its quite likley to trip the auto shutdown temp sensor very quickly

CHR15

It takes about 3 miliseconds to fry a CPU if there is no heatsink on top of it.

Try with your old Graphics card fitted to make sure the rest of the PC is good as nex0 suggests.

Get that sorted first

My GTS250 only has one socket on the card for the power, but it needs TWO supplies, my card came with a splitter.
Simply connecting the PCI-e plug into the card will not make it work.

Mine isn't EVGA though (assume that's the manufacturer) so yours may be different.

Mine needs a LOT more than 24A, I think you are only looking at one 12v line, there are two which should be listed on the side of the PSU


{EDIT}
I just looked at the specs for the EVGA

http://www.evga.com/products/moreInfo.asp?pn=01G-P3-1155-TR



It seems a single supply is all which is needed on that one so 24A should be enough.
.

basmic

CHR15 wrote: »

It takes about 3 miliseconds to fry a CPU if there is no heatsink on top of it.

Absolute cobblers!

http://www.youtube.com/watch?v=pHH6u56iA0E

CHR15

basmic wrote: »

Absolute cobblers!

http://www.youtube.com/watch?v=pHH6u56iA0E

You try it superman. I've seen a CPU burn

Power on..oh !!!!!!, power off.... too late. Couple of seconds tops

saltscar

I put the old graphics card back and it does not boot up, checked the CPU mounts they are ok, the splitter is fitted from PSU to card. Still no boot up. Many thanks for your suggestions guys.