GPU predicament: 290x vs 295x2

[Zaydox]

Hey everyone. So I'm in a little bit of a pickle.

First of all, I'm trying to decide whether to upgrade to a 4k monitor and buy a 295x2 or to save some money and go with a 1440p monitor and buy a second 290x but with 8GB of VRAM (and obviously a new PSU to meet my requirements, for both options).

If I choose the former, I'll be down a bit of money.

If I choose the latter, I'll have some extra money in my pocket. However, I might have a heat issue on my hands. Herein lies the problem.

I'm currently using a MicroATX motherboard, and two 290x cards running in immediate proximity may cause some airflow/heating issues for one of the cards (I think; tell me if I'm wrong about this). Liquid cooling both cards would cost me equal to, if not more than the cost of the first option, but with lower quality hardware. Buying a new motherboard would be just barely less expensive that the first option, but with a huge amount of hassle involved. I would prefer to avoid this if possible.

Thanks in advance.

-Z

Edit: Just heard that with the advent DX12/Mantle, VRAM will stack up while in crossfire/SLI. Perhaps I should just grab another 4GB 290x card.
Edit 2: Here's my build: https://pcpartpicker.com/b/7bZ8TW

 

[jerdle]

No point in pairing an 8GB 290X with a 4GB 290x.

Either get another 4GB version, or wait for the 300 series in june.

 

[Zaydox]

No point in pairing an 8GB 290X with a 4GB 290x.

Either get another 4GB version, or wait for the 300 series in june.

Well the obvious point would be to have 8GB of accessible VRAM... rather than just 4GB.
Unless you're refering to something that I have to guess at.

Any other suggestions?

Edit: I think that I'm probably going to go with the 290x card because I don't want to split my CPU into x8, x4, and x4 buses.
My predicament now lies within which card to get (8GB or 4GB), and whether to buy a new motherboard...

 

[Sergeant_Sneaky]

No point in pairing an 8GB 290X with a 4GB 290x.

Either get another 4GB version, or wait for the 300 series in june.

Well the obvious point would be to have 8GB of accessible VRAM... rather than just 4GB.
Unless you're refering to something that I have to guess at.

Any other suggestions?

If you pair an 8GB card with a 4GB card, it'll either not work or you'll only be able to use 4GB of the VRAM on both cards as they mirror each other.

 

[Karadjgne]

Sli/crossfire doesn't add vram, if you have 2x 4Gb cards, you only have 4Gb. If you add an 8Gb card to a 4Gb card you have 4Gb (if it works)

No matter what monitor, a 295x2 8Gb will out perform CF 290x 4Gb, you'd have to have CF 290x 8Gb to do better than a 295x2 8Gb.

As far as heat goes, the 295x2 with clc cooling is far superior than CF 290x, since all the associated heat from a 295x2 is shunted directly out of the case, whereas CF 290x drops that heat right back into the case, which as said, can create thermal problems, especially in a smaller case with an aircooler cpu.

Get the 295x2. It'll handle the 4k monitor better than most, has no worries pushing a 1440p, has almost no heat issues inside a case, and on a u ATX board, alleviates a lot of possible space issues.

Or wait for the 300 series, which from the looks of things will have its own liquid cooling possibility

 

[Zaydox]

Sli/crossfire doesn't add vram, if you have 2x 4Gb cards, you only have 4Gb. If you add an 8Gb card to a 4Gb card you have 4Gb (if it works)

No matter what monitor, a 295x2 8Gb will out perform CF 290x 4Gb, you'd have to have CF 290x 8Gb to do better than a 295x2 8Gb.

As far as heat goes, the 295x2 with clc cooling is far superior than CF 290x, since all the associated heat from a 295x2 is shunted directly out of the case, whereas CF 290x drops that heat right back into the case, which as said, can create thermal problems, especially in a smaller case with an aircooler cpu.

Get the 295x2. It'll handle the 4k monitor better than most, has no worries pushing a 1440p, has almost no heat issues inside a case, and on a u ATX board, alleviates a lot of possible space issues.

Thanks for the info, but will the 295x2 split up my PCI lanes too thinly? If they're like x8, x4, and x4, will it not bottleneck two of the GPUs?

Also, for now, the 295x2 is a 4GB card (except on Mantle). The 8GB is split between the 2 GPUs.
Which is why I brought up the fact that DX12 may stack up VRAM.

But I do agree with you as far as cooling goes.

 

[jerdle]

I still don't think you understand what we have been saying...
Give yourself a pop quiz:
If you get an 8gb 290x and xfire it with your 4gb 290x, you will have how much vram?

The correct answer was 4GB.

Thus there is no point to getting an 8gb version of a 290x if you already have a 4gb version.

Two normal 290x cards will do well in both 1440p and 2160p.

 

[Karadjgne]

A 295x2 is a single card, in a single x16 slot. The only difference architecturally between the 295x2 and the majority of other cards is that a 295x2 has a dual gpu design. It has 2x slightly undercooked r9 290 gpus on 1 card running a hardwired internal version of crossfire. There is no splitting up of pcie lanes, it runs on a single x16. It's 1 card, not 2. And you won't add it to your 290x, you replace the 290x with it and sell the 290x.

That's it, 1 video card in 1 slot working by itself.

The r9 295x2 is an 8Gb card, there aren't any 4Gb versions that I've ever seen, and both internal gpus share that 8Gb, its not 2x4Gb like crossfire 290x would be 4Gb vram.

 

[uglyduckling81]

A 295x2 is a single card, in a single x16 slot. The only difference architecturally between the 295x2 and the majority of other cards is that a 295x2 has a dual gpu design. It has 2x slightly undercooked r9 290 gpus on 1 card running a hardwired internal version of crossfire. There is no splitting up of pcie lanes, it runs on a single x16. It's 1 card, not 2. And you won't add it to your 290x, you replace the 290x with it and sell the 290x.

That's it, 1 video card in 1 slot working by itself.

The r9 295x2 is an 8Gb card, there aren't any 4Gb versions that I've ever seen, and both internal gpus share that 8Gb, its not 2x4Gb like crossfire 290x would be 4Gb vram.

Nothing else to add to this. Explains it perfectly.
If you don't get it after reading this one it's time to take your PC to a computer shop and say can you improve performance for me? Here is my budget.

 

[jerdle]

Actually, it is 4gb per GPU.

it is exactly like 290x in crossfire would be like.

IIRC, there is one mantle game that can use same frame rendering, which would give both it and the 290x 4gb in crossfire 8gb effective. In 99% of cases though, it has 4gb of effective memory.

 

[Karadjgne]

1 thing to add. I'm not sure of the 4k performance of the Titan X, but the r9 295x2 was (last that I knew anyways) undisputed king of 4k gaming. There may be some exceptions to this like quad-290x etc, but for a single card nothing could touch it.

 

[Karadjgne]

Not that I knew. The gpus on a 295x2 work in tandem basically like a raid hdd from 8Gb. With CF 290x both gpus work in tandem and both vram works in tandem, so 2x raid. The 8Gb on a 295x2 isn't in tandem with anything, what you basically get is a double power gpu using an ahci 8Gb of ram, vrs a double power gpu using a raid 4Gb vram.
Not quite the same.