HD3870 undetected by motherboard

veheATI · Feb 16, 2008, 08:55 AM

Hi...
Just receive my HD3870....
my mobo is Asus A8R-MVP...
tried to replace my 7900GS...
but when i start up...long continuous beep...(which i believe means video pb?)
fans are turning....

something related to PSU? 18A on 12V, i iknew it was low, but i thought it would still start...

any ideas?

thx

Judas · Feb 16, 2008, 11:39 AM

18amp on the pci-ex connector (it's own rail) or is that 18amp overall? If it's the later, your psu is not going to cut it.

kris23 · Feb 16, 2008, 01:31 PM

i think its the whole 12v rail.... hey man, ur going to need something around 26A minimum, the recommended is 30A but you should go higher if you can, i think my PSU has a 38A rail so im probably good for 2 cards but thats a bare minimum for 2 just so you know.

veheATI · Feb 16, 2008, 06:27 PM

yep, it's 18A on the whole rail...
so it seems that I'm very far from the minimum requirements...
damnit, i'll have to spend another 80 bucks....

[hobo]eclipse · Feb 16, 2008, 07:58 PM

to be honest, taking into acount the other thread, even after the 3870 and new PSU your performace will not be that much better IMHO.

kris23 · Feb 16, 2008, 08:01 PM

i guess..... but its still better, lol

OldBuzzard · Feb 16, 2008, 10:04 PM

Quote:

Originally Posted by veheATI

yep, it's 18A on the whole rail...
so it seems that I'm very far from the minimum requirements...
damnit, i'll have to spend another 80 bucks....

In that $$ range, the Corsair 450VX will do what you need and more. Plus it's quality is second to none.

450VX and it's bigger 'brothers' here:
Newegg.com - Computer Parts, PC Components, Laptop Computers, Digital Cameras and more!.

Grace's DH Review of the 450VX: http://www.driverheaven.net/reviews/Corsair%20VX450W/

kris23 · Feb 16, 2008, 10:05 PM

corsair makes a nice PSU man....

[hobo]eclipse · Feb 16, 2008, 11:11 PM

yas i was lookin at a corsair for a future upgrade

blueacolyte · Feb 17, 2008, 07:50 AM

Hey, you don't need to spend that much... Antec Earthwatts 380w (34amps on 12V) at Newegg for $35 + free shipping.

Newegg.com - Antec earthwatts EA380 ATX12V v2.0 380W Power Supply 100 - 240 V UL, CUL, FCC, TUV, CE, CB, C-tick, CCC - Retail

veheATI · Feb 17, 2008, 08:57 AM

Quote:

Originally Posted by blueacolyte

Hey, you don't need to spend that much... Antec Earthwatts 380w (34amps on 12V) at Newegg for $35 + free shipping.

Newegg.com - Antec earthwatts EA380 ATX12V v2.0 380W Power Supply 100 - 240 V UL, CUL, FCC, TUV, CE, CB, C-tick, CCC - Retail

Hey thanks! that looks like a sweet deal...25 euros for me! alas they dont ship international...

the same one in Europe is 45 euros...ah well it's still half what I planned....cool

@[hobo]eclipse: I will start like that and later upgrade to Opteron (175)...that are still available in Europe...and may rise to the level of X2 4800+....

kris23 · Feb 17, 2008, 03:04 PM

i wouldnt get that PSU if i were you......
thats a multi-rail PSU. you dont just go adding up the rails.... sorry but thats nowhere near the actual 12v amperage....

actually 34A at 12v is physically impossible to create by that unit...... you may not even get anywhere with that unit because it sounds too similar to what you have right now.

my recommendation: spend the money and get a PSU properly fitted to your machine or you run the risk of killing all your hardware

veheATI · Feb 19, 2008, 09:00 AM

Turns out it was a stupid mistake of mine....
The system did start...
It's been a few days since I'm gaming heavily (COD4) every night without troubles....
A lot of people have told me that a total of 18A (216W) won't be near enough to power the system....
but the figures are showing a different story.
The 3800+ (Venice Core) is annouced at 89W...but real world test show that under stress, the power consumption is around 30W (this cpu is veru efficient)
as for the CG...from Xbit labs, under load the card is sucking around 80-90W.
I have one HD...that should be around 10W...
so we are at a total of: 130W underload....
that leave 80W for the motherboard and keyboard mouse and fans....which should be enough....
There is the efficiency of the PSU to take into account, I think though...

So far I haven't seen any signs of weakness...I have some issues when certain games, when the card refuse to work at its fullest (GPU usage wont go to 100%) but it seems to be driver-related, as if I change the driver version (from 8.2 to 7.12), the GPU work at its fullest....which show I think it's not a PSU issue.

I just wanted to share that with you guys...(and maybe you will point something wrong in my argument, and my PSU will burn soon

)...because not all of us have a lot of money...when I sell out 200 euros for a card and then I realize I need to spend even more to get it to work, it's embarrassing, especially if that wasn't that necessary....

Judas · Feb 19, 2008, 09:29 AM

There is such things as overhead...

the fact is that 18amp is riding the edge, is likely the source of any issues your likely seeing including the inability for it to increase it's GPU speed.... or any other oddities.

I've seen it, several times, get a good PSU, as that one will likely result in your hardware frieing oventually....

Coolermasters 500 watt dual rail psu's are quite excellent. Plenty of power, decent price.... and have performed exceptionally well.

Witchfinder · Feb 19, 2008, 05:51 PM

Quote:

Originally Posted by veheATI

Turns out it was a stupid mistake of mine....
The system did start...
It's been a few days since I'm gaming heavily (COD4) every night without troubles....
A lot of people have told me that a total of 18A (216W) won't be near enough to power the system....
but the figures are showing a different story.
The 3800+ (Venice Core) is annouced at 89W...but real world test show that under stress, the power consumption is around 30W (this cpu is veru efficient)
as for the CG...from Xbit labs, under load the card is sucking around 80-90W.
I have one HD...that should be around 10W...
so we are at a total of: 130W underload....
that leave 80W for the motherboard and keyboard mouse and fans....which should be enough....
There is the efficiency of the PSU to take into account, I think though...

So far I haven't seen any signs of weakness...I have some issues when certain games, when the card refuse to work at its fullest (GPU usage wont go to 100%) but it seems to be driver-related, as if I change the driver version (from 8.2 to 7.12), the GPU work at its fullest....which show I think it's not a PSU issue.

I just wanted to share that with you guys...(and maybe you will point something wrong in my argument, and my PSU will burn soon

)...because not all of us have a lot of money...when I sell out 200 euros for a card and then I realize I need to spend even more to get it to work, it's embarrassing, especially if that wasn't that necessary....

Well i had a different card but a low 12v A PSU it used to run my card but the heat from the PSU was real bad also i got a lot lower frame rates
I would really suggest a better PSU as you risk damaging your card and PSU
I got a Corsair i can highly recommend them i too didnt want to pay out the extra money but it was worth it.