PCI Express 3.0 GPUs not working in 2.0 slot motherboard?

[ibn5000]

Hello, recently my friend lent me his GTX 1050 after he upgraded it to a 1080ti. I have a PCI-Express 2.0 motherboard from asus(P5Q), 8gb of ram ddr2 and a 450watt powersupply.

I saw around the forum that PCI 3.0 GPUs should work in a 2.0 motherboard, But when i set everything up. the PC turns on for Half seconds with all fans and then it shutdown and it repeats over and over.

 

[dextermat]

Hi,

Your power supply is too weak you need ate least a good 600 w

source

 

[ibn5000]

thats actually not my question

 

[Mattp2017]

Yes it should work find in a PCI-E 2.0 slot.

 

[Karadjgne]

Many 10 series cards have issues with legacy bios since the card uses a uefi vbios. The only possible fixes I've ever heard of are in your mobo bios disable Secure boot, enable CSM and disable fast boot of any sort.

It's not a slot issue, pcie 2.0 and 3.0 are identical except 3.0 has larger bandwidth capabilities. I believe it's a bios/vbios compatability issue between your obvious legacy bios and a uefi gpu. This issue started with the gtx750/ti and affects the 9/10 series cards too.

 

[nico.k]

thats actually not my question

also that's not true, my 400W beQuiet is pwoering my 1070 just fine.

 

[Karadjgne]

Recommended sizes:

1050ti: 350w
1060: 450w
1070: 500w

Recommended sizes are just that, recommended. The actual size needed can vary depending on the pc used. A basic 2 fan, i3, 2 drive is only going to run @100w-150w at most, add in a 75w 1050ti and maximum torture test usage on cpu and gpu is only going to be @175w-225w for the whole pc. That's a long way from an older 125w Vishera FX cpu with a decent OC that'll push over 300w with ease under torture. 350w is recommended for the simple reason that not all psus are equal, so you'd go with a larger 350w/450w if the psu was mediocre, but could just as easily go with a high grade 250w/350w

Thats why the 1070 works with a 400w psu. Your actual outlay of power is closer to 350w maxed.

Absolutely no reason for a 600w psu for a gtx1050ti unless it's Super Junk like Apevia or Huntkey or Sharkoon or others, where whatever the claimed number is, count on it being @50% of that.

 

[RememberThe5th]

My 1050ti works without issue on G31M-S2L.
I find that weird.
And to mention on cheap-o MS-400W ATX.

 

[Karadjgne]

Not wierd at all. Some cards have better adaptability than others and will work on legacy bios mobo's just fine. Other cards just seem to balk at the prospect. It all depends on the vbios in that respect. There's also 3 types of bios right now. Legacy, hybrid and uefi. Hybrid bios is mostly 3rd party ppl like HP that were in the middle of the switch and used a legacy bios on a uefi platform. Plays havoc with gpus. Disabling secure boot, enabling CSM (sorta like a compatability mode) and disabling any fastboot can sometimes overcome the issues, but with the old legacy stuff and 9/10 series or Rx series cards it's a crap shoot.

If it won't work no matter if bios is fully updated, any and all fixes are tried, best bet would be a switch/trade for a gtx770/780, which will work as intended.