Totally perplesed

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Hi all, need some advice.

Since beginning of the year, I've changed my case, bought new mobo, cpu and memory, and bought an Asus Radeon 6850. My PSU is an Akasa PowerMax 850w.

Mobo: Asus P8Z68-VLX

Processor:INTEL Core i5 2500K

Memory: CORSAIR 8GB.

Without doing War & Peace, I've had a lot of problems.

When I first set this up, the pc refused to boot. It won't even get to POST. I subsequently returned first the memory (seller said it tested ok). then the mobo, memory and cpu. Seller returned the lot, saying it all tested OK. The system still refused to boot.

I then returned the GPU. This was returned to Asus (via RMA) who said it was faulty and sent me a replacement. My system still refused to boot. Having RMA'ed the second GPU, it's being returned to me as the sellers (not a million miles from here :p) say it works fine.

The best suggestion I have is to submit my machine to a local techie for hardware tests. I have no complaints about Overclockers, or their service.

My problem is that I'm not sure what spending £50ish with a local techie is going to prove. I spent that much earlier on in this process and the guy I saw couldn't find a problem. I should point out that the system works perfectly well with my old Asus Radeon 4850 (which I'm currently using).

So, confusion reigns. I really need some guidance here:

1. Should I try a local guy?

2. Is the PSU up to the job (I believe it is).

3. Should I cut my losses, sell the 6850 & buy a different Manufacturers model (taking a loss).

4. Am I missing something really obvious.

The card will be landing here sometime tomorrow (Tuesday) and I'd appreciate any advice that can be offered.

Thanks,

Confused of Wilts :D
 
I think if the system works with the 4850 but not with the 6850 it has to be either the video card or the PSU. Defintaely all cabled up ok with the PCI-E power lead(s)

If so, given you've got a replacement 6850, that just leaves the PSU. Did you get it with the rest of your new kit? Its not uncommon for them to fail in weird ways, like for example with something that draws a bit more power than before.

I bought PSU last year, it has 3 years warranty. I have no idea how to test it though. I was using it on my last rig with no problems
 
Might have the solution?

Ok guys, been doing research and I need any opinion & suggestions.

I now suspect my PSU isn't providing enough power on the 12v rail. The PSU is an Akasa PowerMax 850w:

http://www.bit-tech.net/custompc/reviews/129287/akasa-powermax-850w.html

AS stated, GPU is Asus Radeon 6850.

I've now discovered that the Radeon needs a minimum of 500w power supply with at least a 40A 12v rail and 2x6pin power connectors. Problem is, the Akasa site above says that the 12v rail works as follows:

"Each of these 12V rails is rated as being capable of supplying up to 35A, and they distribute their load as follows: 12V1 powers the motherboard, half of the CPU, two of the PCI-E cables and the Molex ports, while 12V2 powers the other half of the CPU, the other two PCI-E cables and the S-ATA ports"

So, am I correct in thinking that the reason the PC won't boot is because there's not enough power going to the 6850? Assuming that's the case, can anyone recommend me a reasonably priced PSU that will do 40a 12v rail. It doesn't have to be 850w, as long as it does what I need!

All opinions/advice gratefully accepted.

Rob
 
Looking @ manual, but not ure what you mean. Sorry, not very good w this aspect of PCs, but really appreciate yr help.

This is the manual online:

http://akasa.co.uk/update.php?tpl=p...supplies&type_sub=Performance&model=AK-P085FG

What should I be looking for?

Having read a bit, I think that although the 2 12v rails can go to a quoted 64a, the power is being shared between various components, which leaves the GPU short of juice, meaning the pc won't boot?
 
Application 850W PC Power Supply
Designed for AMD / INTEL based systems
ATI / NVIDIA graphics
Form factor ATX12V 2.2 & EPS12V 2.92
Dimension 150 x 160 x 86mm
Typical efficiency 85.49% (80.89% at full load)
Power factor correction Active PFC
Fan 135 x 135 x 25mm, dual ball bearing, 600-1800RPM
Motherboard connectors 1 (20+4pin)
ATX12V connectors 1 (4+4pin)
8/6-pin PCIe 2 (6+2pin)
PCIe 6pin connectors 2
SATA connectors 6
Molex 4pin connectors 6
FDD 4pin connectors 2
Cables finish Black mesh (all cables, full length)
AC power input Full range 100V to 240V (auto switching)
Protection Over Power / Voltage / Current / Temperature
Short Circuit
Safety UL, TUV, CE, FCC, CB, N, D, FI, S
Product code AK-P085FG-BKUK (UK)
AK-P085FG-BKEU (Europe)

PowerMax 850W Output Specification
Rail +3.3V +5V +12V1 +12V2 -12V +5Vsb
Maximum Wattage 180W 768W 3.6W 15W
Maximum Load 25.0A 30.0A 35.0A 35.0A 0.3A 3.0A
64A

The manual doesn't give much more info than this
 
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