to Crossfire or not to Crossfire

[Silent Spring]

hi all

i was thinking of crossfiring my ATI Radeon HD 5770 with another ATI Radeon HD 5770

im a bit of a noob the pc in my sig was my fisrt build.

so not sure if it is worth xfiring

how to do it?

etc

so just some tips and pointers

thanks

 

[MoRT489]

Loads of people on this forum have done so, skim read this thread http://forums.overclockers.co.uk/showthread.php?t=18072807

 

[bhavv]

More that 100% woth crossfiring the 5770 if you can.

You just buy a second card, install it to the second slot, plug in the crossfire connecter, reinstall drivers and you're set.

 

[straxusii]

Not sure your PSU is up to it?

 

[Silent Spring]

Not sure your PSU is up to it?

no im not sure either

 

[OCP]

I'm pretty sure your PSU can handle it no problem. Theres a pretty nifty power calculator you can use which gives you a rough idea how much your rig is pulling.

 

[phod]

Im not sure your motherboard supports 8x/8x on the 2 pci-e slots, probably best to read your motherboard manual to find out if your board supports crossfire and at what rates.

 

[MoRT489]

ur second PCIe slot runs at 4x, this will cost u about 10-15% performance hit IIRC but it would still be worth doing crossfire.

THe power consumption these things is so low i thing 500W (good brand) would be fine.

 

[theforce]

ur second PCIe slot runs at 4x, this will cost u about 10-15% performance hit IIRC but it would still be worth doing crossfire.

THe power consumption these things is so low i thing 500W (good brand) would be fine.

I had the impression that the second PCIe slot only run at 4x on P35 motherboards. Is it the same with P45 and P55?

 

[marley82]

I dont think 500w is enough for a overclocked i5 and 2 HD5770's. It will boot yes but I think you'll have problems when gaming, Go for a 650w Corsair if you can.

 

[Legion]

I had the impression that the second PCIe slot only run at 4x on P35 motherboards. Is it the same with P45 and P55?

The cheaper P55 mobo's have a second physical 16x slot that is only 4x electrical.

You have to spend a bit more and double check before you hit the buy button to make sure you are buying an 8x/8x board.

Yes it's stupid as the P55 natively supports 8x/8x,it's just another way to squeeze more money out of you by manufacturers.

Cheapest Asus board to do this is the P7P55D PRO.
Gigabyte is UD4.

The rest you'd have to do your own homework on,just make sure you know what you are buying

 

[Meaker]

Yeah but a 4x slot on p55 is gen 2 and will be gen 1 on the p35.

Running two heavily OCed HD 4770 I get near 0 difference in performance.

 

[PrincessFrosty]

Yeah first check mobo specs see if you can get x16 on both PCI ports at the same time, it may not matter depending on the speed of them cards actually.

Then look into PSU requirements.

Other than that you just need to order a 2nd card, plug it in, possibly reinstall drivers and thats about it, it's actually really simple if you've done your homework on the hardware before hand.

 

[Silent Spring]

thanks all i will have a read up of the motherboard manual 2nite

 

[Silent Spring]

- 500W Configuration
- OCZ PowerWhisper™ Technology
- Internal 120mm fan
- 3 year warranty backed by OCZ’s exclusive PowerSwap™ replacement program. No more endless return-for-repair loops!
- 150 x 140 x 86mm 1 x 20+4Pin ATX
- 1 x 4-pin CPU
- 1 x PCI-E 6+2 pin
- 4 x 4-pin Molex peripheral
- 1 x 4-pin floppy
- 2 x S-ATA
- High efficiency
- 80% @ 115V (Typical load)
- 83% @ 230V (Typical load)
- Overvoltage/Overcurrent/Short-Circuit protection
- Active PFC
- MTBF:100,000 hours
- 100~240Vac 10-5A 50/60Hz
- +3.3V(36A), +5V(30A), +12V1(18A), +12V2(18A), +12V3(18A), +12V4(18A)


reckon i will have to change my power supply anyway as its only got on pc1 e power socket.

unless the cards came with an adaptor whach i cant remember have to look when i ge home

 

[PrincessFrosty]

You can get 2 molex to 1 PCIE 6pin adaptors, a lot of card still come with them.

But total power draw is still a primary concern.

 

[Silent Spring]

yes i are right of course i will check when home by downloading some sort of power draw software

 

[reflux]

You'll need to be running 1680x1050 or above to make it worthwhile.