I have a LillyGo TTGO T-beam v1.1 that I bought from an Amazon seller (OneMoTime).
The device was working for about a day, when I noticed it was frozen. Upon reset, it would not boot.
I hooked it up tp my laptop and used the esphome-flasher to connect to the console log - and I see the following repeat over and over:
[21:04:10]Rebooting...
[21:04:10]ets Jul 29 2019 12:21:46
[21:04:10]
[21:04:10]rst:0xc (SW_CPU_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
[21:04:10]configsip: 0, SPIWP:0xee
[21:04:10]clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
[21:04:10]mode:DIO, clock div:2
[21:04:10]load:0x3fff0018,len:4
[21:04:10]load:0x3fff001c,len:1044
[21:04:10]load:0x40078000,len:8896
[21:04:10]load:0x40080400,len:5828
[21:04:10]entry 0x400806ac
[21:04:11]E (1486) spiram: SPI SRAM memory test fail. 130178/131072 writes failed, first @ 3F800120
[21:04:11]
[21:04:11]E (1486) cpu_start: External RAM failed memory test!
[21:04:11]abort() was called at PC 0x4008293e on core 0
[21:04:11]
[21:04:11]ELF file SHA256: 0000000000000000
[21:04:11]
[21:04:11]Backtrace: 0x4008feaf:0x3ffe3be0 0x40090235:0x3ffe3c00 0x4008293e:0x3ffe3c20 0x40079053:0x3ffe3c40 0x400790b9:0x3ffe3c70 0x400790c4:0x3ffe3ca0 0x4007928d:0x3ffe3cc0 0x400806de:0x3ffe3df0 0x40007c15:0x3ffe3eb0 0x4000073d:0x3ffe3f20
[21:04:11]
[21:04:11]Rebooting...
I was able to re-flash the firmware - even tried a few different versions - but had the same end result.
I am pretty sure this is a hardware defect - but wanted to check here in case I am wrong.