Topic: Two 5870's or one 5970? (Read 2335 times)

I'm currently mining with a GTX 570 twin frozr III. Not ideal I know but it is what I currently own and just wanted to test the whole mining thing before spending some money on a new card. I can happily get to sleep with this running at full clock speed at night. Thats why I thought a non reference might have similar db levels.

Unfortunately this is not a computer specifically for mining. Maybe one day but not for now. This is also my day to day computer so has to stay in my room. This leaves me with three options.

Either I get the best card or cards I can with the greatest OC potential to produce the largerst Mhash/s I can. This option will obviously create alot of noise due to fan speed so will only be able to run from about 8.00 in the morning to about 11.00 at night. My worry with this option is what effect constantly disconnecting from the pool will have on the amount of BTC I recieve as appose to option 2.

My second option is to get something that will run quite enough for me to get to sleep, at the cost of mhash/s, so I can run it 24/7. No worries with this one really I just feel my next option is better.

My third option, which I feel is the best option, is to go with option one but lower the clocks at night, to a suitable level, so the fans can run near idle speed. My only worry with this one is the amount of kwh I will use but I feel this difference will be negligable.

Also water cooling is not an option at this current time as it is too much exspense.

without a fan you only get 50Mh/s

Sleep? No way!

I tried (5970), tried again... then I put miner in wooden box outside on balkony.

Don't do it. Noise can cause serious health issues.

Think FPGA, maybe? No fan at all

keep an eye on overclockers.co.uk. they were doing brand new 5850s for £99 last week. they were sold out pretty quickly. I can't see the listing anymore, but who knows - maybe they ordered more

the 5970 I have seen is not new. It's apparently refurbished and comes with a 12 month warranty with the company who refurbished it. I've looked into them and although there service isn't perfect theres alot of people who have dealt succesfully with them.

The 5870's I have seen are with the same company at £120 each. Again refurbished with 12 months warranty.

Both the cards I have mentioned are cheaper than anywhere else and they are reference cards which are getting hard to find. If I do decide against purchasing from them I have seen some new 5850 non reference sapphire cards for £115 each (I dont think you can really buy new reference ones anymore). Granted they wont have much OC potential but at least I will have the peace of mind that I am getting what I pay for and they are new. Buy second hand and they most likely wont have any warranty and who knows what kind of abuse they have had. Put them in a mining rig running 24/7 and they might not last a week. Could last for years but it is a gamble.

I have two of these in one rig:
http://www.overclockers.co.uk/showproduct.php?prodid=GX-147-XF&groupid=701&catid=56&subcat=1711

They are doing 420Mh/s each at 71 C and 76 C. Fans at 100% plus two extra fans which I don't think are necessary but I like to keep temps as low as possible. Room temperature get's about 5-7 degrees warmer - I keep windows open all the time. The whole rig is consuming ~350W. They are fucking loud and I can't sleep anymore.

That 5970 for 250 sounds way too good to be true - I'd stay away. In fact I haven't seen brand new 5970 for sale anywhere in UK

I have a 5870 and 5850 in my rig currently, both overclocked, and with an average combined hashrate of 770 MH/s. They cost me a total of $330. It seems that 2 cards are a better deal, both in performance and cost/MH/s. I do not know about power usage, but this thread (http://forums.atomicmpc.com.au/index.php?showtopic=264) says that a 5970 will consume a maximum of of 299 watts at load, while CrossFired 5870s can consume up to 399 watts total (but again, better performance and OC ability).

I think I should be able to manage the noise as I've realised I could just run at lower clocks and fan speed at night then up it again before I go to work.

There is someone advertising a refurbished 5970 for £250 with a 12 month warranty. Seems a bit too good to be true but if all checks out ok I may get this and heres why.

Although people say you can get a better hash rate with 5870's, from what I read the 5970 consumes less power so end result shouldn't be too different. The main reason though is because I've got sandybridge components on the way with the asus z68 pro board. This only has 1x PCIe x16, 1x PCIe x8 and 1xPCIe x4 (I think this slot is also tied to the usb 3.0 and something else but I wouldn't be using either of these). If I go dual 5870's I'm a little worried about how the x4 PCIe slot will effect performance. I have read that people think this shouldn't have too much effect on mining but couldn't find any substantial proof. So with this in mind if I can get the 5970 cheap enough I will get that but if not I will go for the 5870's and hope for the best.

Thanks you all for your advise.

I have a 5970 mining about 720 Mhash/s (360 per core) with poclbm under Ubuntu linux 11.04 64 bit.  Right now, the GPUs are overclocked to 810mhz and fan is spinning at 3460 rpm with temp at 73C.  I increased that from stock fan speed using AMDOverdriveCtrl.  I can hear it running from twenty feet away; it's noticeable but not distracting.  Higher fan speed equals cooler GPU.  You can fiddle with the fan controls to find a place you're comfortable with.  BTW, I think there's more hash potential with the 5970 but I was getting lock-ups around 850 Mhz core speed.

+100500
 

5970 only had better PCI-e slot utilisation.
in other terms 2x 5870 was better.
and you also save about 40% cash, cuz 5870 stay erroneously overpriced last 2 years.

The 5870's will hash faster with stock clocks than the 5970, by about 10-15%.  Dollar for hash, the 5870 is probably quite a bit cheaper.

But if you buy a 5970, you've left a slot open on your motherboard in case you later acquire another graphics card.  So then you can start mining with it without needing to buy more MB/CPU/RAM/PS.  That benefit offsets the 5870's lower price per hash.

Both will put out large amounts of heat - be ready for that.

Dual 5870s should be louder, in fact, than a 5970, but also potentially run cooler.

And generally, non reference cards suck, unless it is a special aftermarket cooler, not the crap that sapphire and the like put on the cards.

Lol where are you getting those prices from mate because here in the uk the 5970 is £400 minimum and the 5870 is £140 minimum ?

Should I get two 5870's or one 5970?

I'm trying to decide what to do. I can Either get two non reference 5870's or one 5970. Either setup will initialy cost me exactly the same (£250). The 5970 will use less watts but the 5870's will be quiter.

I have the computer in my room and have it mining 24/7. I'm leaning more towards the non reference 5870's so that I might actually be able to get to sleep at night. Would the 5970 be unbearable. Does anyone have one who could comment?