Bitcoin Forum

Bitcoin => Bitcoin Technical Support => Topic started by: NeonFlash on September 24, 2011, 06:38:09 AM



Title: What CPU to choose for my GPU?
Post by: NeonFlash on September 24, 2011, 06:38:09 AM
The mining will be done by GPU ofcourse. But, let's say I put one of the heavy duty GPUs like ATI Radeon HD 5870 on my MB. Would it make a difference if I have an i5 (2nd Gen) processor or a i7 (2nd Gen) processor along with it?

I am trying to go for a cheaper CPU to invest more on the GPU, but wanted to get your suggestions before :)

Just wanted to ensure that my CPU doesn't bottleneck the performance of my GPU.

Also, the stats put on the wiki's mining hardware comparisions don't give details of the other hardware parts like CPU, so am not sure if I can expect the same hashing rates as what is updated on the wiki for an ATI Radeon HD 5870 GPU.

Thoughts?


Title: Re: What CPU to choose for my GPU?
Post by: wumpus on September 24, 2011, 06:56:15 AM
For gaming it matters a lot but, for mining you could just put in a 486, its only job is busy-waiting for the GPU anyway :-)


Title: Re: What CPU to choose for my GPU?
Post by: Revalin on September 24, 2011, 07:46:09 AM
Choose whichever is cheapest and has the lowest idle power draw, because it's going to be 99% idle.


Title: Re: What CPU to choose for my GPU?
Post by: Lord F(r)og on September 24, 2011, 08:49:54 AM
Choose whichever is cheapest and has the lowest load power draw, because it's likely to be 99% loaded if you plan to use multiple gpus with windows.

for example look here: https://bitcointalk.org/index.php?topic=43604.40


Title: Re: What CPU to choose for my GPU?
Post by: NeonFlash on September 24, 2011, 09:47:25 AM
Thanks for the details. I came across this link which shows a comparison between power consumption numbers for different processors under various scenarios (idle, system load, cpu load).

http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/44339-intel-core-i3-2120-core-i5-2400-lga1155-processors-review-16.html


Title: Re: What CPU to choose for my GPU?
Post by: Lord F(r)og on September 24, 2011, 01:12:39 PM
a nice comparison to get an idea fo what power consumtion will be on actual hardware, but you don't have to spend lots-o-$ for the newest stuff. when mining its all about the efficency and it begins with the costs for hardware. so if you just want to mine buy "old" hardware for cheap. for example a Sempron 140 + board with pci-e will do. think twice: don't underrate powercosts! check there if it's worth mining for you: http://bitcoinx.com/profit/ or if it's better to invest $ directly in btc.


Title: Re: What CPU to choose for my GPU?
Post by: Remember remember the 5th of November on September 24, 2011, 02:33:47 PM
I can tell you, if you are getting an AMD processor, it must be faster than the Phenom II 955 cause as of now, this CPU even at 3.4Ghz bottlenecks the 5870(at stock clocks).


Title: Re: What CPU to choose for my GPU?
Post by: Lord F(r)og on September 24, 2011, 02:57:48 PM
I can tell you, if you are getting an AMD processor, it must be faster than the Phenom II 955 cause as of now, this CPU even at 3.4Ghz bottlenecks the 5870(at stock clocks).

whoot? but how is this https://bitcointalk.org/index.php?topic=34591.msg430737#msg430737 possible? and all the other numerous sempron 140 rigs?


Title: Re: What CPU to choose for my GPU?
Post by: Remember remember the 5th of November on September 24, 2011, 03:02:54 PM
I can tell you, if you are getting an AMD processor, it must be faster than the Phenom II 955 cause as of now, this CPU even at 3.4Ghz bottlenecks the 5870(at stock clocks).

whoot? but how is this https://bitcointalk.org/index.php?topic=34591.msg430737#msg430737 possible? and all the other numerous sempron 140 rigs?
I meant this for gaming, it's no trouble to get a cheap sempron, but if the PC was ever to be used for anything other than mining, that CPU will just not do.


Title: Re: What CPU to choose for my GPU?
Post by: deslok on September 24, 2011, 03:05:08 PM
I can tell you, if you are getting an AMD processor, it must be faster than the Phenom II 955 cause as of now, this CPU even at 3.4Ghz bottlenecks the 5870(at stock clocks).

If you have issues at stock with a 5870 something else is wrong even a e-350 handles it fine, (just noticed you added a comment about it being for gaming)
if you're worried about power load with multiple gpu's get a cheap, modern multi core cpu and manually set the cpu afinity to a single core you're power draw will be lower since you're only loading one and the system will be more responsive if you use something like logmein since the other core(s) are idle


Title: Re: What CPU to choose for my GPU?
Post by: Lord F(r)og on September 24, 2011, 03:06:09 PM
I can tell you, if you are getting an AMD processor, it must be faster than the Phenom II 955 cause as of now, this CPU even at 3.4Ghz bottlenecks the 5870(at stock clocks).

whoot? but how is this https://bitcointalk.org/index.php?topic=34591.msg430737#msg430737 possible? and all the other numerous sempron 140 rigs?
I meant this for gaming, it's no trouble to get a cheap sempron, but if the PC was ever to be used for anything other than mining, that CPU will just not do.

agreed of cause


Title: Re: What CPU to choose for my GPU?
Post by: NeonFlash on September 24, 2011, 05:40:08 PM
Ok, speaking of using the cheapest processors out there with the latest GPUs for the purpose of mining.

I want to be able to reuse as many components from my old PC in this new one for mining rig. I don't use the Old PC for any purpose at this point.

Can I use an Intel Pentium 4 Processor 3.0 Ghz with an ATI Radeon HD 5870 GPU?

Another point here. The ATI Radeon HD 5870 GPU requires a latest motherboard. But will an Old CPU go on the processor sockets on the latest Motherboards?


Title: Re: What CPU to choose for my GPU?
Post by: deslok on September 24, 2011, 07:54:46 PM
Ok, speaking of using the cheapest processors out there with the latest GPUs for the purpose of mining.

I want to be able to reuse as many components from my old PC in this new one for mining rig. I don't use the Old PC for any purpose at this point.

Can I use an Intel Pentium 4 Processor 3.0 Ghz with an ATI Radeon HD 5870 GPU?

Another point here. The ATI Radeon HD 5870 GPU requires a latest motherboard. But will an Old CPU go on the processor sockets on the latest Motherboards?

Cpu's only go into sockets they were designed for, if that pentium 4 is a socket 775 model you can purchase motherboards that will allow you to use a pci express graphics card with it. Any cpu that is compataible with a pci express equiped motherbaord can be used for mining