[REMA1]

Hej son just got a new GPU for his Birthday.

His xfx 7870 will crossfire with the one I have in my rig BUT is the
Amd Phonem PII x4 965 BE choking it. ( I know 1 higher spec card card is better than 2, but the 7870 is there )
Temps are fine . CPU is still around 40-45 c in crossfire and the cards are typically 82 and 76 C in Unigine Heaven. (have a large Phantex double fan cooler on it.) Here there is approx 10fps increase in xfire.

In benchmark tests in Theif, Dirt 3, Mafia II the cards are cooler BUT I see very little difference in fps ...literally a couple of frames...BOTH cards are running and xfire is enabled.

SO cpu the cause?...did OC cpu from stock 3.4 to 3.7 but no real difference.

thanks for your thoughts

 

[ebackhus]

Some games just don't take advantage of multi-GPU setups. The 7870 is getting a bit long in the tooth and with game updates sometimes affecting the engine you could see performance fall over time.

 

[Frost_Byte]

The HD 7870 is an R7 270, so it's still very viable. If you have a motherboard that will accept a better processor something in the order of an FX 8320/8350 yes you can definitely get better frames, though I would eventually look for a better single card instead of 2 HD 7870's. Something like an R9 290. You may ask why and it's because a single card configuration draws less power, and is far more compatible with most games VS. running in a crosssfire config as pointed out above.

 

[bassfisher6522]

Temporary work around until you get a new CPU or new mobo/cpu; is to OC that CPU. If you don't want to mess with OC'ing in the BIOS, you can do it with AMD's CCC software (that's how I did mine). With an old Hyper 212 cpu cooler, I OC'd my CPU from stock 3.4 Ghz to 4.2 Ghz and it ran beautifully for 2 years. Yes...there is a significant boost in game play.

I have that same exact CPU and love it, it's in my son's rig.

 

[REMA1]

thanks for the replies all....although I bought this motherboard ( gigabyte 790X - GA-790XTA-UD4 )several years EFTER I'd bought an asus that takes ddr2 ram , and which subsequently was upgrade via the bios to use amd3+ processor , this gigabyte mobo with it's ddr3 ram and USB 3 ports...WILL NOT accept an amd 3+ processor...
apparently the space on the BIOS isn't big enough..

I'd just assumed it would....One day I WILL BUILD A PC AND KEEP IT..
It gets to the last few components and I think ....well my son will have more use of this than me...I can have his old one....guess I'm not alone by a long chalk in this "faulty "behaviour.
anyway I be backs again ..guess it will be new mobo and gpu at sometime in the future...I'll be back!

Oh and my amd 965 be (125W) OC to 3700 stable , maybe 3800 using BIOS multiplier...I don't tend to mess with voltages on it though. Temps are usually 45 C under load...50C with crossfire running...BUT I do have a dirty BIG
PH-TC14PE CPU Cooler sitting on top of it...(in a sale , really cheap at the time)