Does PCI-E 2.1 work on PCI-2.0 slot?

[KyleGP]

I'm in the market for my new card.

I'm keen on the Asus Directcu card, but it's PCI-E 2.1.

My motherboard is a Gigabyte EP-45 DQ6 and is PCI-E 2.0.

Does that mean I need a PCI-E 2.0 card, or less, but I can't use 2.1?

 

[hunter315]

Yes, PCI-E is fully backwards and forwards compatible between versions, you can use any PCI-E card in any PCI-E 16x slot, it doesnt matter if the card or slot is 1.x or 2.x.

 

[wa1]

Yes, don't worry about that. just like hunter said above...

 

[irfan88]

But can i really connect a HD 5770 (PCI-E 2.0 Card) on my XFX nforce 630i Motherboard (PCI-E 1.0a slot). Will it work?

 

[wa1]

If you have 2.0 card then you shouldn't worry, but if you have 2.1 card, well, there's many issue on 2.1 card running on 1.0 slot motherboard...

 

[RazberyBandit]

Yes, PCI-E is fully backwards and forwards compatible between versions, you can use any PCI-E card in any PCI-E 16x slot, it doesnt matter if the card or slot is 1.x or 2.x.

Wrong. While PCIe 2.1 is fully compatible with older 1.x and 2.0 versions, motherboards do require BIOS updates to support PCIe 2.1 cards. We've run into this problem on these forums many times over the last few months with people who purchased ATI 5000-series cards (all of which are PCIe 2.1) for older systems, many of which were pre-built Brand-Name systems from Acer, Dell, etc., and most of which contained motherboards that had lost support several years ago, prior to PCIe 2.1 being accepted as the next standard.

While his specific motherboard does not fall into that category, such a blank statement is false. The correct answer is: Not always. PCIe 1.0, 1.0a, and 2.0 motherboards may require a BIOS update for PCIe 2.1 card compatibility.

 

[irfan88]

all ATI 5000 cards are not 2.1. Please check as XFX HD 5700 is 2.0 whereas Asus HD 5700 is 2.1, MSI is 2.0 etc. Please revert ASAP and I dont think that XFX nforce 630i motherboard is too old. It is still available in the computer markets and it does support a geforce 8800 GT ultra which is 2.0.

 

[RazberyBandit]

You are also wrong. XFX 5700-series cards are not PCIe 2.0, they simply have PCIe 2.0 support built-in, making the motherboard's own support for PCIe 2.1 a non-factor. Read their product descriptions for yourself here and here at the bottom of the "KEY FEATURES" section.

My guess is you looked it up on Newegg, who just happens to advertise these cards as PCIe 2.0 cards, when in fact all 5000-series cards are PCIe 2.1.

 

[irfan88]

So ho much of power supply is required for a 2.1 card to work in a 1.0 slot. Please suggest me a PSU for upgrading in both of these cases:

1) for connecting only 1 card
2) for connecting it in a cross fire mode.

Thanks

 

[RazberyBandit]

It's not a matter of power making a 2.1 card work within a 1.0 slot, it's a matter of the BIOS being able to recognize a 2.1 card for what it is and actually initialize the device. In order to do that, it needs to be updated. But few 1.0 and 1.0a slotted motherboards received such updates because they're no longer actively supported by the manufacturers due to their age.

I've spoken with XFX techs about this issue in the past for a friend. Here's one of my support discussions:

[ 4/7/2010 7:04:22 AM] I was hoping you guys could help me out with something else, though. It`s not related to my card, but to a card a friend of mine purchased for his old PC. It was an XFX HD-545X-YNH2 HD 5450 he wanted to install to turn his old HP machine into an HTPC. We couldn`t get it to work at all, though. Through some research on the web, we found it`s actually pretty common for these new ATI PCIe 2.1 cards to fail to be recognized in older systems with PCIe 1.0 or 1.0a x16 slots. Can you shed any light on that matter for me? Is there a work-around of any sort? Most 1.0 and 1.0a motherboards have since lost support, especially pre-built PCs from makes like HP, Acer, Compaq, etc., so there`s no way to get any help from them... Not even a BIOS update. It definitely wasn`t the motherboard. His old 7300LE still worked, and so did 2 of my cards. (8800GT and HD4850)

[BRIAN 4/7/2010 6:48:21 PM] Hi, I`m working on the verification for you. As for the other issue, what is the chipset of the motherboard that he is putting it into? Also, you may want to have him contact HP and flash the motherboard to the latest BIOS on his board. Thanks, Brian.

[BRIAN 4/7/2010 7:10:44 PM] Hi, I got an email back from my webadmins and they have verified your account. You`re all set. Thanks, Brian.

[ 4/7/2010 11:56:35 PM] The motherboard of the HP machine we tried putting the 5450 in is an ASUS-made A8AE-LE with an RS482 chipset. ASUS made these as OEM parts for HP, and unfortunately neither one has a newer BIOS update than what`s already installed on it. I tried re-flashing it with same version in hopes something had changed over the years since it`s release - it hadn`t and still failed to initialize the card. Here`s a link to the actual board: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00496280+tmp_task=prodinfoCategory+lc=en+dlc=en+cc=us+lang=en+product=1831231 I tend to think he`s stuck going back a generation to a 4550 due to it being a PCIe 2.0 card. What he wanted was to get a card with true Dolby streaming, which the 5450 has. Through my own searches on the web, it seems 5000-Series PCIe 2.1 cards just don`t work in a lot of 1.0 motherboards. It just doesn`t make any sense that it`s not fully backwards compatible.

[DANIEL_E 4/9/2010 6:18:52 PM] Hi, unfortunately if that`s the case you`d either need to change the motherboard out or go with a different model card. Daniel

[ 4/9/2010 10:47:34 PM] By different model card, I guess you mean an older generation, as other people have experienced this same issue with 5670 and 5770 cards. I`m looking for an explanation why this happens. PCIe 2.1 cards are supposed to be backwards compatible, just as 2.0 cards are. The primary reason he chose a 5450 card was because of it`s ability to stream Dolby TrueHD and DTS audio. 4000-series cards don`t offer that, so the incentive to use them is lacking. Thanks.

[MARK_C 4/13/2010 1:07:57 AM] Hello XXXXXXX, We don`t have an explanation of why. That is just the way that it is. The motherboard manufacturer didn`t implement the proper support before discontinuing support for the product. Some of them did and some did not. It happens when new standards come out. If he wants those features I would recommend using a GeForce G 210 or GT 220. They have the same audio controller that the 5450 does and are about the same performance. Thank you. Mark

[ 4/13/2010 7:13:47 AM] Thanks for the reply and alternative suggestions, Mark. My friend was able to return it without incurring any restocking fee. I`ll pass along the recommendations. Feel free to close this ticket.

[MARK_C 4/15/2010 12:46:43 AM] Let us know if you need anything else. Thank you. Mark

He recommended a GT210/220 because those cards are PCIe 2.0 and all ATI 5000-series cards are PCIe 2.1. Pick-up the phone and call them for yourself. In North America, call 800-880-3225 9am - 5pm PST.


Regardless, the OP has a more modern motherboard with a PCIe 2.0 slot, and therefore should be able to use PCIe 2.1 cards.

 

[distiller]

i'm having the same problem with a 5450.

i chose it for the same reasons mentioned above as well as it only taking up one slot since it's passively cooled.

it'll work alright until it gets blisteringly hot and then it crashes and my monitor goes into sleep mode.

i'm using an asus P5QPL-AM, which is not an old motherboard, and when i use the onboard video, everything works a treat. all parts are brand new out of the box BTW and, i've flashed the bios to the latest rev. from the asus website.

do i need to buy another card? i can't use some behemoth card since it's a HTPC.

it's my first build as well so, a little disappointing when you think you've done yer homerk and you walk into a quirk like this one.

 

[godslam]

Wrong. While PCIe 2.1 is fully compatible with older 1.x and 2.0 versions, motherboards do require BIOS updates to support PCIe 2.1 cards. We've run into this problem on these forums many times over the last few months with people who purchased ATI 5000-series cards (all of which are PCIe 2.1) for older systems, many of which were pre-built Brand-Name systems from Acer, Dell, etc., and most of which contained motherboards that had lost support several years ago, prior to PCIe 2.1 being accepted as the next standard.

While his specific motherboard does not fall into that category, such a blank statement is false. The correct answer is: Not always. PCIe 1.0, 1.0a, and 2.0 motherboards may require a BIOS update for PCIe 2.1 card compatibility.

I'd like to thank you. I was stumped as to why my thing wasn't working correctly. I usually don't update BIOS 'cause I'm a bit lazy and it usually doesn't affect me much. This helped a ton though. Thanks.

 

[Mousemonkey]

This topic has been closed by Mousemonkey