GPU in PCIe x4 slot

Hi there!

Here's the story... I got a PC for a really great price (free, can't beat that!). It's a mini-ITX system with an Atom on board (Asus AT5NM10T-I) and just happens to have an open ended PCIe 4x (x1 mode).

Now, I figured I could give this nice little box to my 7 y.o. so he doesn't need to pester me or my wife to watch some videos or play a flash game or two. Since there's the PCIe slot, I started thinking about getting a cheapo GPU - something that has more muscle than the onboard GMA3150, so he can get some HD content playback and perhaps do some very, VERY light gaming.

Now, as stuoid as it might sound, I wanted to double check if it'll actually accept a GPU. Sadly, that's a field where I don't have much experience, heh. Does the x4_1 slot has enough juice for a low end GPU?

Cheers and thanks!


V.

At x1, I think even a low end GPU is going to be bottlenecked...

just for video playback x1 isnt going to be problem imo, if it is on pcie 2.0 a x1 slot is going to have 500mb/s. a GT430 or ATI 6450 would be a good fit imo, i have no problems with the GT430 doing BD playback.

When I was looking into crossfiring with 6850s on my board (second pci-e16 lane runs at 4x) I found benchmarks, and was told anecdotally that the second card would lose about 4-8 percent performance due to bottlenecking. Which really isn't that horrible.

1.0 would be a serious bottle neck for newer midrange cards but you would still get a lot more features than you would with the GMA, and you will improve system performance since video will not use shared memory.

Check your bios to see if "Video adapter" lets you disable it or select PEG mode for the slot. If not than it may not function at all. You could still try, and would only be out $30 tops on a used video card.

4x=1GBps one way so if low powered you will be fine. I added a 2400XT PCI (not PCIe) card to my kids p4 era PC and it made a noticeable difference) and thats 133MBps bandwidth.

Thanks for all the replies guys! Much appreciated!

@Evilsizer: You're pretty much nailed it. Those are the cards I was looking at, roughly.

@others: The slot is PCIe 2.0 4x in x1 mode, as ASUS calls it, which, I assume, is the same as x1 electrical, which, I guess it's a single lane of 500Mbps.

The thing I'm totally unsure about is how much power can the slot supply. I assume it's less than full size x16?
The other thing I've no clue about, is what to add up, to figure out how much bandwidth the card needs. I'd like to know how much I would be loosing
Thanks!

ETA:
The spare screen I have is an old 17" ViewSonic, so the max resolution will be 1280x1024, I suppose that is relevant
Also, The PSU in the box is a cheapo 300W one, which isn't enough for HD6450 from what I read. GT430 still looks good tho!

1x electrical slot according to JEDEC only supplies 10W.

But I see a few 1X cards with no external power.. so cant be sure.

6450 1gb uses half the power of a 430 (30W to 60w) and is about 60% the performance of the 430 except at higher resolutions when the 1GB memory has the advantage.

If your 300W produces even 100W it should be more than enough. I ran a 2500K and 3650 on a 250W no name SFF PSU.

Neuromancer said:

Card with external power is a good idea, as the 1x electrical slot according to JEDEC only supplies 10W.

6450 1gb uses half the power of a 430 (30W to 60w) and is about 60% the performance of the 430 except at higher resolutions when the 1GB memory has the advantage.

Click to expand...

Hmmm, yeah, will have to look for one with external power then... I'm just somewhat skeptical I'll find any card in this price range that would come with external power.

Also I just checked BIOS and it offers two options PCIE/IGD or just IGD. So I assume a discrete card should work in the PCIE/IGD mode.

As far as GT430 vs HD6450 goes... Yeah, I could be wrong, I just checked specs in some reviews and saw that HD6450 has a 400W PSU recommendation while GT430 has 300W. Either way, I suppose that's irrelevant now...

updated my post external power might not be necessary since none of the cards listed on newegg use them. I would go with the 6450. You can get them new for $20 AMIR in the US, not sure about Europe.

Neuromancer said:

updated my post external power might not be necessary since none of the cards listed on newegg use them. I would go with the 6450. You can get them new for $20 AMIR in the US, not sure about Europe.

Click to expand...

Hmm, as per wikipedia:

Power
PCI Express cards are allowed a maximum power consumption of 25W (×1: 10W for power-up). Low profile cards are limited to 10W (×16 to 25W). PCI Express Graphics 1.0 (PEG) cards may increase power (from slot) to 75W after configuration (3.3V/3A + 12V/5.5A).[9] PCI Express 2.1 increased the power output from an x16 slot to 150W so that some high-performance graphics cards can be run from the slot power alone.[10] Optional connectors add 75W (6-pin) or 150W (8-pin) power for up to 300W total.

Click to expand...

Now, I'm not a native English speaker, but it seems to me x1 doesn't deliver just 10W... puzzling

Eh, I can only dream about US prices over here. A new 512Mb HD6450 costs $38. Didn't even bother checking 1Gb version.

the way i read it, the pcie slot will do 75watts total. doesnt say it is based on 1x,2x,4x,8x,16. now i could have read it wrong but i have seen people run x16 slot cards in 8x slots with no problem. being at work right now i cant go looking much at the specs, but if i recall right the power connection is all up front for the first set of pins. then the rest of the pins after it are just for the data pins.

Evilsizer said:

the way i read it, the pcie slot will do 75watts total. doesnt say it is based on 1x,2x,4x,8x,16. now i could have read it wrong but i have seen people run x16 slot cards in 8x slots with no problem. being at work right now i cant go looking much at the specs, but if i recall right the power connection is all up front for the first set of pins. then the rest of the pins after it are just for the data pins.

Click to expand...

But, but, but... Work is like... THE place, to do things that are more interesting than work

Just kidding, of course. Thanks for the help!

Yes, that's pretty much how I read it too... Besides, there are workstation graphics, which, AFAIK, also run on 4x with x1 electrical. Just don't wanna end up with a useless card that is being all useless on me.

So, besides GT430 and HD6450, is there anything else worth looking at?

well the new 6xx from NV but they use the same chip in the lower-end. meaning your better off buying a the older 4xx line vs paying a bit more for just a name change. ATI has not come out with the new 7450 or lower end parts from the 7 series yet. leaving you only with the 6xxx parts for the lowerend cards.

right now it is just a waiting game for ati for new lower end parts. as far as NV goes, if you want the new kepler core in the lower end on the retail side is GT640 retail or getting the OEM parts.

Evilsizer said:

well the new 6xx from NV but they use the same chip in the lower-end. meaning your better off buying a the older 4xx line vs paying a bit more for just a name change. ATI has not come out with the new 7450 or lower end parts from the 7 series yet. leaving you only with the 6xxx parts for the lowerend cards.

right now it is just a waiting game for ati for new lower end parts. as far as NV goes, if you want the new kepler core in the lower end on the retail side is GT640 retail or getting the OEM parts.

Click to expand...

Well, a GT640 might be an "overkill" considering pretty much any card will bottleneck on that slot. Might as well go with the cheapest option...

And, I've finally come across some more information regarding x1 slots. They do provide the same W as x16. However, there could be problems with BIOS supporting a card that runs at lower clocks as it's supposed to. Then again, the PCIe on this ASUS board is open-ended from factory, so I assume they're expecting people to use "longer" cards in there...

Given that a 5870 looses ~25% in a PCIe 2.0 1x slot, I don't think a GT640 will lose all that much.
Overkill? Maybe.
Even with a bottleneck it'll give better performance than a lower end card.

Bobnova said:

Given that a 5870 looses ~25% in a PCIe 2.0 1x slot, I don't think a GT640 will lose all that much.
Overkill? Maybe.
Even with a bottleneck it'll give better performance than a lower end card.

Click to expand...

That's good to know! From what I was told previously, even the low end of the lowest end would receive a performance hit...

Sadly, I will have to stick with a lower end card. Money's tight at the moment. I want to replace to noname case and PSU, and I've been meaning to get myself a GPU for awhile now too... damn retailers over here keep pushing up the price of HD6950 ~$20 up in a week...

Sorry for double post...

If i can get a hd4670 for the price of a hd6450, is that a no-brainer and I should get the 4670 since it's (vastly?) superior to hd6450?

well given atom performance as a cpu, really getting a 4670 is going to be a waste even more so at x1 pcie connection. for me had no problems playing alice maddness returns with things on high at 720p. there might have a been some fps drops that could be noticed by some sluggishness in turning in certian areas. what gpu im talking about is the GT430 i used on my i7 vs atom, fps will be more of a challange.

if his gaming is all web based games then it wont be a problem. even older games maybe around 5yrs or so wouldnt be a problem. it just sounds like a lot is expected from the atom setup with x1 slot. if this was say a older amd X2 with onboard or even a core 2 cpu that would be different. i did a atom 230 vs 330 review along time ago, at that time i figured that even at 1.6ghz for the atom. it would take a core 2 around 1-1.2ghz to beat it in performance. both cpus do work in different ways, that atom was setup to be less power hungry which also ment much less performance vs core 2.

my suggestion is still a GT430 (best bet imo) or get the 6450.

v1ks_ said:

Hmm, as per wikipedia:


Now, I'm not a native English speaker, but it seems to me x1 doesn't deliver just 10W... puzzling

Eh, I can only dream about US prices over here. A new 512Mb HD6450 costs $38. Didn't even bother checking 1Gb version.

Click to expand...

That is exactly what I used for my commentary 16x slot delivers up to 25W (actually up to 75w)

1X however only gives you 10W. You have a 4X physical with an open back and a 1X electrical. Difference between 1X and 16x isnt DATA its all power. At least that is my understanding since every other pin is a ground.

I dont know. I do but this conversation is an old one. Im pretty sure you cant expect 75W from a 1X electrical slot since A) the only cards available are totally crappy 10W versions. b) The pinout does not support it. according to JEDEC standards.

I might be wrong. try it out. Grab a 35W card and pop it in there. Maybe it works. I put a 2400Xt in a PCI slot. it worked great. PCI is waht a 15W slot.

Looked at the PCI slot standards, Amps times volts and came up with less than 15W. and that was rough.

Im saying 1X is enough for bandwidth but not enough power. Feel free to prove me wrong..

Neuromancer said:

That is exactly what I used for my commentary 16x slot delivers up to 25W (actually up to 75w)

1X however only gives you 10W. You have a 4X physical with an open back and a 1X electrical. Difference between 1X and 16x isnt DATA its all power. At least that is my understanding since every other pin is a ground.

I dont know. I do but this conversation is an old one. Im pretty sure you cant expect 75W from a 1X electrical slot since A) the only cards available are totally crappy 10W versions. b) The pinout does not support it. according to JEDEC standards.

I might be wrong. try it out. Grab a 35W card and pop it in there. Maybe it works. I put a 2400Xt in a PCI slot. it worked great. PCI is waht a 15W slot. (hoarish *****)

Looked at the PCI slot standards, Amps times volts and came up with less than 15W. and that was rough.

Im saying 1X is enough for bandwidth but not enough power. Feel free to prove me wrong.. Beleive me I hope you are right. and it provides 75W power. Considering the structure of PCIE, that is not the case, so FX FX FX.

(that means fingers crossed btw)

DEW ehhhhtttt!!!! And tell us. Maybe it works maybe it doesnt. I see the standard is not adhered to. So maybe....

Click to expand...

Aw pooo... waking up to news like these suxx some major dong

When I got this Atom, I was brought 7 PCs, starting from a PIII 800Mhz and the Atom I got being the newest. From one of the rigs my colleague pulled a GeForce 8600, I could ask him if he has put it in already. He took it because he has a PC that he uses to make vector graphic files for his cutting table (no idea what the proper English term is. The thing is fed vector graphic files and it then cuts whatever it's been given out of plywood or other soft materials, aluminium was too hard, iirc). So yeah... I could borrow it, or an old GeForce 6600. I'm quite sure both of them can pull more than 10W...

EDIT:
@Evilsizer: Sorry man, just noticed that you posted too Thanks! It's not like much is expected, it's more like I'm looking around for what is available at what price I do realize that it's an Atom and as such, I shouldn't expect much, despite the fact that 1.8Ghz, two cores and four threads make it sound bad@$$(almost)

Anyway, what worries me the most at the moment, is wether or not the card will work at all. If I understand correctly, Neuro thinks they won't as the slot provides only 10W.... now, so far I've 5 sources or so, that all claim it will work, mostly other forums that came up while googling (No, I swear I am not a member there!!1`!). Granted, most of them are old-ish posts and involve cards like 7600, 7900, 8600 and 8800... but I'm fairly certain even those used more than 10W.

*sigh* what to do...